Hybrid Synergy Drive

Last updated
Hybrid Synergy Drive logo Jb hsd.png
Hybrid Synergy Drive logo

Hybrid Synergy Drive (HSD), also known as Toyota Hybrid System II, is the brand name of Toyota Motor Corporation for the hybrid car drive train technology used in vehicles with the Toyota and Lexus marques. First introduced on the Prius, the technology is an option on several other Toyota and Lexus vehicles and has been adapted for the electric drive system of the hydrogen-powered Mirai, and for a plug-in hybrid version of the Prius. Previously, Toyota also licensed its HSD technology to Nissan for use in its Nissan Altima Hybrid. Its parts supplier Aisin offers similar hybrid transmissions to other car companies.

Contents

HSD technology produces a full hybrid vehicle which allows the car to run on the electric motor only, as opposed to most other brand hybrids which cannot and are considered mild hybrids. The HSD also combines an electric drive and a planetary gearset which performs similarly to a continuously variable transmission. The Synergy Drive is a drive-by-wire system with no direct mechanical connection between the engine and the engine controls: both the gas pedal/accelerator and the gearshift lever in an HSD car merely send electrical signals to a control computer.

Lexus Hybrid Drive logo Lexus hybrid logo.png
Lexus Hybrid Drive logo

HSD is a refinement of the original Toyota Hybrid System (THS) used in the 1997 to 2003 Toyota Prius. The second generation system first appeared on the redesigned Prius in 2004. The name was changed in anticipation of its use in vehicles outside the Toyota brand (Lexus; the HSD-derived systems used in Lexus vehicles have been termed Lexus Hybrid Drive), was implemented in the 2006 Camry and Highlander, and would eventually be implemented in the 2010 "third generation" Prius, and the 2012 Prius c. The Toyota Hybrid System is designed for increased power and efficiency, and also improved "scalability" (adaptability to larger as well as smaller vehicles), wherein the ICE/MG1 and the MG2 have separate reduction paths, and are combined in a "compound" gear which is connected to the final reduction gear train and differential; [1] it was introduced on all-wheel drive and rear-wheel drive Lexus models. [2] [3] By May 2007 Toyota had sold one million hybrids worldwide; two million by the end of August 2009; and passed the 5 million mark in March 2013. [4] [5] As of September 2014, more than 7 million Lexus and Toyota hybrids had been sold worldwide. [6] The United States accounted for 38% of TMC global hybrid sales as of March 2013. [5]

Principle

Toyota 1NZ-FXE engine (left) with early HSD, sectioned and highlighted (right). Generation 1/Generation 2, chained, ICE-MG1-MG2 Power Split Device HSD is shown. Toyota 1NZ-FXE Engine 01.JPG
Toyota 1NZ-FXE engine (left) with early HSD, sectioned and highlighted (right). Generation 1/Generation 2, chained, ICE-MG1-MG2 Power Split Device HSD is shown.

Toyota's HSD system replaces a normal geared transmission with an electromechanical system. An internal combustion engine (ICE) delivers power most efficiently over a small speed range, but the wheels need to be driven over the vehicle's full speed range. In a conventional automobile the geared transmission delivers different discrete engine speed-torque power requirements to the wheels. Geared transmissions may be manual, with a clutch, or automatic, with a torque converter, but both allow the engine and the wheels to rotate at different speeds. The driver can adjust the speed and torque delivered by the engine with the accelerator and the transmission mechanically transmits nearly all of the available power to the wheels which rotate at a different rate than the engine, by a factor equal to the gear ratio for the currently selected gear. However, there are a limited number of "gears" or gear ratios that the driver can choose from, typically four to six. This limited gear-ratio set forces the engine crankshaft to rotate at speeds where the ICE is less efficient, i.e., where a liter of fuel produces fewer joules. Optimal engine speed-torque requirements for different vehicle driving and acceleration conditions can be gauged by limiting either tachometer RPM rate or engine noise in comparison with actual speed. When an engine is required to operate efficiently across a broad RPM range, due to its coupling to a geared transmission, manufacturers are limited in their options for improving engine efficiency, reliability, or lifespan, as well as reducing the size or weight of the engine. This is why the engine for an engine-generator is often much smaller, more efficient, more reliable, and longer life than one designed for an automobile or other variable speed application.

However, a continuously variable transmission allows the driver (or the automobile computer) to effectively select the optimal gear ratio required for any desired speed or power. The transmission is not limited to a fixed set of gears. This lack of constraint frees the engine to operate at its optimal brake-specific fuel consumption. An HSD vehicle will typically run the engine at its optimal efficiency whenever power is needed to charge batteries or accelerate the car, shutting down the engine entirely when less power is required.

Like a CVT, an HSD transmission continuously adjusts the effective gear ratio between the engine and the wheels to maintain the engine speed while the wheels increase their rotational speed during acceleration. This is why Toyota describes HSD-equipped vehicles as having an e-CVT (electronic continuously variable transmission) when required to classify the transmission type for standards specification lists or regulatory purposes.

Power flows

In a conventional car design the separately-excited alternator with integral rectifier (DC generator) and starter (DC motor) are considered accessories that are attached to the internal combustion engine (ICE) which normally drives a transmission to power the wheels propelling the vehicle. A battery is used only to start the car's internal combustion engine and run accessories when the engine is not running. The alternator is used to recharge the battery and run the accessories when the engine is running.

The HSD system replaces the geared transmission, alternator, and starter motor with:

Through the power splitter, a series-parallel full hybrid's HSD system thus allows for the following intelligent power flows: [8]

Power electronics from Prius NHW11 "Classic" ToyotaOpenHSD.jpg
Power electronics from Prius NHW11 "Classic"

MG1 and MG2

  • MG1 (Primary motor-generator): A motor to start the ICE and a generator to generate electrical power for MG2 and to recharge the high voltage traction battery, and, through a DC-to-DC converter, to recharge the 12 volt auxiliary battery. By regulating the amount of electrical power generated (by varying MG1's mechanical torque and speed), MG1 effectively controls the transaxle's continuously variable transmission.
  • MG2 (Secondary motor-generator): Drives the wheels and regenerates power for the HV battery energy storage while braking the vehicle. MG2 drives the wheels with electrical power generated by the engine-driven MG1 and/or the HVB. During regenerative braking, MG2 acts as a generator, converting kinetic energy into electrical energy, storing this electrical energy in the battery.

Transmission

Late Toyota HSD, sectioned and highlighted. Generation 3, chainless, ICE-MG1 Power Split Device/MG2 Motor Speed Reduction Device HSD is shown. This is a P510 transaxle, from a 2012- Prius c; a P410 transaxle, from a 2010-2015 Prius, is similar, but is physically larger; a Generation 4 P610 transaxle from a 2016- Prius is 47mm narrower than a P410 by implementing side-by-side motors rather than end-to-end motors. Toyota electronic continuously variable transmission (2010-10-16) 03.jpg
Late Toyota HSD, sectioned and highlighted. Generation 3, chainless, ICE-MG1 Power Split Device/MG2 Motor Speed Reduction Device HSD is shown. This is a P510 transaxle, from a 2012– Prius c; a P410 transaxle, from a 2010–2015 Prius, is similar, but is physically larger; a Generation 4 P610 transaxle from a 2016– Prius is 47mm narrower than a P410 by implementing side-by-side motors rather than end-to-end motors.

The mechanical gearing design of the system allows the mechanical power from the ICE to be split three ways: extra torque at the wheels (under constant rotation speed), extra rotation speed at the wheels (under constant torque), and power for an electric generator. A computer running appropriate programs controls the systems and directs the power flow from the different engine + motor sources. This power split achieves the benefits of a continuously variable transmission (CVT), except that the torque/speed conversion uses an electric motor rather than a direct mechanical gear train connection. An HSD car cannot operate without the computer, power electronics, battery pack, and motor-generators, though in principle it could operate while missing the internal combustion engine. (See: Plug-in hybrid) In practice, HSD equipped cars can be driven a mile or two without gasoline, as an emergency measure to reach a gas station.

An HSD transaxle contains a planetary gear set that adjusts and blends the amount of torque from the engine and motor(s) as it's needed by the front wheels. It is a sophisticated and complicated combination of gearing, electrical motor-generators, and computer-controlled electronic controls. One of the motor-generators, MG2, is connected to the output shaft, and thus couples torque into or out of the drive shafts; feeding electricity into MG2 adds torque at the wheels. The engine end of the drive shaft has a second differential; one leg of this differential is attached to the internal combustion engine and the other leg is attached to a second motor-generator, MG1. The differential relates the rotation speed of the wheels to the rotation speeds of the engine and MG1, with MG1 used to absorb the difference between wheel and engine speed. The differential is an epicyclic gear set (also called a "power split device"); that and the two motor-generators are all contained in a single transaxle housing that is bolted to the engine. Special couplings and sensors monitor rotation speed of each shaft and the total torque on the drive shafts, for feedback to the control computer. [9]

In Generation 1 and Generation 2 HSDs, MG2 is directly connected to the ring gear, that is, a 1:1 ratio, and which offers no torque multiplication, whereas in Generation 3 HSDs, MG2 is connected to the ring gear through a 2.5:1 planetary gear set, [10] and which, consequently, offers a 2.5:1 torque multiplication, this being a primary benefit of the Generation 3 HSD as it provides for a smaller, yet more powerful MG2. However, a secondary benefit is the MG1 will not be driven into overspeed as frequently, and which would otherwise mandate employing the ICE to mitigate this overspeed; this strategy improves HSD performance as well as saving fuel and wear-and-tear on the ICE.

High voltage battery

High voltage nickel-metal hydride (NiMH) battery of second generation Toyota Prius. Ni-MH Battery 02.JPG
High voltage nickel-metal hydride (NiMH) battery of second generation Toyota Prius.

The HSD system has two principal battery packs, the High Voltage (HV) battery, also known as the traction battery, and a 12 volt lead-acid battery known as the Low Voltage (LV) battery, which functions as an auxiliary battery. The LV battery supplies power to the electronics and accessories when the hybrid system is turned off and the high-voltage battery main relay is off. [11] [12]

The traction battery is a sealed nickel-metal hydride (NiMH) battery pack. The battery pack of the first generation Toyota Prius consisted of 228 cells packaged in 38 modules, while the second generation Prius consisted of 28 Panasonic prismatic nickel metal hydride modules, each containing six 1.2 volt cells, connected in series to produce a nominal voltage of 201.6 volts. The discharge power capability of the second gen Prius pack is about 20 kW at 50% state of charge (SoC). The power capability increases with higher temperatures and decreases at lower temperatures. The Prius has a computer that's solely dedicated to keeping the battery at the optimum temperature and optimum charge level. [13]

Like the second generation Prius, the third generation Prius battery pack is made up of the same type of 1.2 volt cells. It has 28 modules of 6 cells for a total nominal voltage of only 201.6 volts. A boost converter is used to produce 500 volt DC supply voltage for the inverters for MG1 and MG2. [11] The car's electronics only allow 40% of total rated capacity of the battery pack (6.5 ampere-hour) to be used in order to prolong the battery life. As a result, the SoC is allowed to vary only between 40% and 80% of the rated full charge. [11] The battery used in the Highlander Hybrid and the Lexus RX 400h was packaged in a different metal battery casing with 240 cells that deliver high voltage of 288 volts. [13]

EV mode button in the 2012 Toyota Camry hybrid. Camry Hybrid 2012 07 VA 4177.JPG
EV mode button in the 2012 Toyota Camry hybrid.

A button labelled "EV" maintains electric vehicle mode after being powered on and under most low-load conditions at less than 25 mph (40 km/h) if the traction battery has enough charge. This permits all-electric driving with no fuel consumption for up to 1 mi (1.6 km). However, the HSD software switches to EV mode automatically whenever it can. [14] [15] Only the Toyota Prius Plug-in Hybrid has a longer driving all-electric range in blended operation electric-gasoline of 11 mi (18 km) (EPA rating) until the battery is depleted. [16] The Prius PHEV is outfitted with 4.4 kWh lithium-ion batteries co-developed with Panasonic that weighs 80 kg (180 lb) compared with the nickel-metal hydride battery of the third generation Prius, which has a capacity of only 1.3 kWh, and weighs 42 kg (93 lb). The larger battery pack enables all-electric operation at higher speeds and longer distances than the conventional Prius hybrid. [17] [18]

The following table details the HV battery capacity for several Lexus and Toyota vehicles. [19]

VehicleModel
Year		Battery
Capacity
(kWh) [19] 		Battery TypeBattery Charge Limit
(kW) [20] 		Battery Discharge Limit
(kW) [21]
Lexus CT 200h 20111.3NiMH
Lexus ES 300h 20131.6NiMH
Lexus ES 300h 20211.6Li-ion
Lexus GS 450h 20131.9NiMH
Lexus IS 300h 20131.6NiMH-28,524
Lexus LC 500h 20181.1Li-ion
Lexus LS 600h L 20081.9NiMH
Lexus RX 450h 20141.9NiMH
Lexus NX 300h 20151.6NiMH-2725,5
Toyota Avalon Hybrid 20131.6NiMH
Toyota Auris Hybrid 20141.3 [11] NiMH-2521
Toyota Camry Hybrid 20141.6NiMH-2725,5
Toyota Camry Hybrid20181.6 / 1.0NiMH / Li-ion
Toyota C-HR Hybrid20161.3NiMH-31,921
Toyota Corolla Hybrid20191.4 / 0.75NiMH / Li-ion-31,921
Toyota Highlander Hybrid 20141.9NiMH
Toyota Mirai (FCV)20151.6 [22] NiMH
Toyota Prius 20101.3NiMH-2521
Toyota Prius20161.2 / 0.75NiMH / Li-ion-31,921
Toyota Prius c 20140.9NiMH
Toyota Prius v 20141.3 / 1.0NiMH / Li-ion
Toyota Prius PHV 20144.4 [18] Li-ion
Toyota Prius Prime 20168.8Li-ion
Toyota RAV4 20151.6NiMH-2725,5
Toyota RAV4 20191.6NiMH (2020- Li-ion)-3824
Toyota RAV4 Prime 202018.1Li-ion
Toyota Yaris Hybrid 20140.9 [23] NiMH-17,515
Toyota Yaris Hybrid 20200.76Li-ion-3520
Toyota Innova/Kijang Innova Zenix Hybrid 20221.31NiMH

Operation

The HSD drive works by shunting electrical power between the two motor generators, running off the battery pack, to even out the load on the internal combustion engine. Since a power boost from the electrical motors is available for periods of rapid acceleration, the ICE can be downsized to match only the average load on the car, rather than sized by peak power demands for rapid acceleration. The smaller internal combustion engine can be designed to run more efficiently. Furthermore, during normal operation the engine can be operated at or near its ideal speed and torque level for power, economy, or emissions, with the battery pack absorbing or supplying power as appropriate to balance the demand placed by the driver. During traffic stops the internal combustion engine can even be turned off for even more economy.

The combination of efficient car design, regenerative braking, turning the engine off for traffic stops, significant electrical energy storage and efficient internal combustion engine design give the HSD powered car significant efficiency advantages—particularly in city driving.

Phases of operation

A typical Hybrid Synergy Drive configuration Prius2004HSD.JPG
A typical Hybrid Synergy Drive configuration

The HSD operates in distinct phases depending on speed and demanded torque. Here are a few of them:

Lexus Hybrid Drive Lexus GS450h 03.JPG
Lexus Hybrid Drive

Performance

The Toyota Prius has modest acceleration but has extremely high efficiency for a midsized four-door sedan: usually significantly better than 40 mpg (US) (5.9 L/100 km) is typical of brief city jaunts; 55 mpg (4.3 L/100 km) is not uncommon, especially for extended drives at modest speeds (a longer drive allows the engine to warm up fully). This is approximately twice the fuel efficiency of a similarly equipped four-door sedan with a conventional power train. Not all of the extra efficiency of the Prius is due to the HSD system: the Atkinson cycle engine itself was also designed specifically to minimize engine drag via an offset crankshaft to minimize piston drag during the power stroke, and a unique intake system to prevent drag caused by manifold vacuum ("pumping losses") versus the normal Otto cycle in most engines. Furthermore, the Atkinson cycle recovers more energy per cycle than the Otto because of its longer power stroke. The downside of the Atkinson cycle is much reduced torque, particularly at low speed; but the HSD has enormous low-speed torque available from MG2.

The Highlander Hybrid (also sold as the Kluger in some countries) offers better acceleration performance compared to its non-hybrid version. The hybrid version goes from 0–60 mph in 7.2 seconds, trimming almost a second off the conventional version's time. Net power is 268 hp (200 kW) compared to the conventional 215 hp (160 kW). Top speed for all Highlanders is limited to 112 mph (180 km/h). Typical fuel economy for the Highlander Hybrid rates between 27 and 31 mpg (8.7–7.6 L/100 km). A conventional Highlander is rated by the EPA with 19 city, 25 highway mpg (12.4 and 9.4 L/100 km respectively).

Cutaway display of the HSD Note: Generation 1/Generation 2, chained, ICE-MG1-MG2 Power Split Device HSD is shown Toyota Paris 9.JPG
Cutaway display of the HSD Note: Generation 1/Generation 2, chained, ICE-MG1-MG2 Power Split Device HSD is shown

The HSD mileage boost depends on using the gasoline engine as efficiently as possible, which requires:

Most HSD systems have batteries that are sized for maximal boost during a single acceleration from zero to the top speed of the vehicle; if there is more demand, the battery can be completely exhausted, so that this extra torque boost is not available. Then the system reverts to just the power available from the engine. This results in a large decline in performance under certain conditions: an early-model Prius can achieve over 90 mph (140 km/h) on a 6 degree upward slope, but after about 2,000 feet (610 m) of altitude climb the battery is exhausted and the car can achieve only 55–60 mph on the same slope.[ citation needed ] (until the battery is recharged by driving under less demanding circumstances)

Prius Platform Generations

The design of the Toyota Hybrid System / Hybrid Synergy Drive has now had five generations since the original 1997 Japanese-market Toyota Prius. The power train has the same basic features, but there have been a number of significant refinements.

Toyota Hybrid System transmissions [27]
ModelGen.Traction motor (MG2)EngineApplications
ModelPowerTorqueModelPowerTorque
Front-wheel drive (transaxle)
P110G11CM30 kW (40 hp)305 N⋅m (225 lbf⋅ft) 1NZ-FXE 43 kW (58 hp)102 N⋅m (75 lbf⋅ft)
P111G12CM33 kW (44 hp)350 N⋅m (260 lbf⋅ft) 1NZ-FXE 53 kW (71 hp)115 N⋅m (85 lbf⋅ft)
P112G23CM50 kW (67 hp)400 N⋅m (300 lbf⋅ft) 1NZ-FXE 56 kW (75 hp)110 N⋅m (81 lbf⋅ft)
P210G1 (SM)1EM [lower-alpha 1] 13 kW (17 hp)110 N⋅m (81 lbf⋅ft) 2AZ-FXE 96 kW (129 hp)190 N⋅m (140 lbf⋅ft)
P310G31JM123 kW (165 hp)333 N⋅m (246 lbf⋅ft) 3MZ-FE 155 kW (208 hp)288 N⋅m (212 lbf⋅ft)
P311G32JM105 kW (141 hp)270 N⋅m (200 lbf⋅ft) 2AZ-FXE 110 kW (150 hp)190 N⋅m (140 lbf⋅ft)
P313G34JM123 kW (165 hp)335 N⋅m (247 lbf⋅ft) 2GR-FXE 172–183 kW (231–245 hp)317 N⋅m (234 lbf⋅ft)
6JM123 kW (165 hp)335 N⋅m (247 lbf⋅ft) 2GR-FXS 193 kW (259 hp)335 N⋅m (247 lbf⋅ft)
P314G32JM105 kW (141 hp)270 N⋅m (200 lbf⋅ft) 2AR-FXE 112 kW (150 hp)206 N⋅m (152 lbf⋅ft)
P410G33JM60 kW (80 hp)207 N⋅m (153 lbf⋅ft) 2ZR-FXE 73 kW (98 hp)142 N⋅m (105 lbf⋅ft)
5JM
P510G31LM/ 2LM45 kW (60 hp)169 N⋅m (125 lbf⋅ft) 1NZ-FXE / -FXP 54 kW (72 hp)111 N⋅m (82 lbf⋅ft)
P610G41NM53 kW (71 hp)163 N⋅m (120 lbf⋅ft) 2ZR-FXE 72 kW (97 hp)142 N⋅m (105 lbf⋅ft)
1NM + 1SM [lower-alpha 2] +23 kW (31 hp)+40 N⋅m (30 lbf⋅ft)
P710G43NM88 kW (118 hp)202 N⋅m (149 lbf⋅ft) A25A-FXS 131 kW (176 hp)221 N⋅m (163 lbf⋅ft)
P711G43NM88 kW (118 hp)202 N⋅m (149 lbf⋅ft) M20A-FXS 107 kW (143 hp)188 N⋅m (139 lbf⋅ft)
P810G45NM134 kW (180 hp)270 N⋅m (200 lbf⋅ft) A25A-FXS 130–140 kW (170–190 hp)221–243 N⋅m (163–179 lbf⋅ft)
P810-IG45NM134 kW (180 hp)270 N⋅m (200 lbf⋅ft) 2GR-FXS 193 kW (259 hp)335 N⋅m (247 lbf⋅ft)
P910G41NM59 kW (79 hp)141 N⋅m (104 lbf⋅ft) M15A-FXE 67 kW (90 hp)120 N⋅m (89 lbf⋅ft)
PA10G51VM70 kW (94 hp)185 N⋅m (136 lbf⋅ft) 2ZR-FXE 72 kW (97 hp)142 N⋅m (105 lbf⋅ft)
PB10G51VM83 kW (111 hp)206 N⋅m (152 lbf⋅ft) M20A-FXS 112 kW (150 hp)188 N⋅m (139 lbf⋅ft)
PB12G51VM120 kW (160 hp)208 N⋅m (153 lbf⋅ft) M20A-FXS 111 kW (149 hp)188 N⋅m (139 lbf⋅ft)
Rear-wheel drive
L110 / L110FG3 (RWD)1KM147–165 kW (197–221 hp)275–300 N⋅m (203–221 lbf⋅ft) 2UR-FSE 280–290 kW (380–390 hp)510–520 N⋅m (380–380 lbf⋅ft)
2GR-FSE 217 kW (291 hp)368 N⋅m (271 lbf⋅ft)
2GR-FXE 217 kW (291 hp)356 N⋅m (263 lbf⋅ft)
L210 / L210FG3 (RWD)1KM105 kW (141 hp)300 N⋅m (220 lbf⋅ft) A25A-FXS 135 kW (181 hp)221 N⋅m (163 lbf⋅ft)
2AR-FSE 131 kW (176 hp)221 N⋅m (163 lbf⋅ft)
2GR-FXE 217 kW (291 hp)356 N⋅m (263 lbf⋅ft)
L310 / L310FG4 (RWD)2NM132 kW (177 hp)300 N⋅m (220 lbf⋅ft) 8GR-FXS 220 kW (300 hp)356 N⋅m (263 lbf⋅ft)
Notes
  1. ↑ Single-motor variant omits MG2 and uses MG1 only
  2. ↑ Transmission equipped with a one-way clutch to permit dual-motor operation with MG1 and MG2

Generation 1 (Toyota Hybrid System)

Schematic diagram of the First- and Second-Generation Toyota Hybrid System transaxle (P110/ P111/ P112): S: Central "'sun" gear P: Planetary gear carrier R: Outer ring gear 1: Motor-Generator 1 2: Motor-Generator 2 E: Internal Combustion Engine G01 & G02 Toyota Hybrid System.svg
Schematic diagram of the First- and Second-Generation Toyota Hybrid System transaxle (P110/ P111/ P112):
  • S: Central "'sun" gear
  • P: Planetary gear carrier
  • R: Outer ring gear
  • 1: Motor-Generator 1
  • 2: Motor-Generator 2
  • E: Internal Combustion Engine

The system was called the Toyota Hybrid System (THS) when it was introduced with the Prius in 1997. [28] The hybrid transaxle, designated P110, [29] includes two electric motors (MG1 and MG2) and a planetary gearset, which Toyota calls the "Power Split Device" (PSD); mechanical power from the internal combustion engine (E) can be directed either to the wheels or to MG1, acting as a generator. [28]

Electrical power flows between MG1, MG2, and a storage battery through an inverter. Although MG1 typically operates as a generator (alternator), it also serves as the starter motor for the internal combustion engine. MG2 usually acts as a motor, either by itself at low speeds or to assist the internal combustion engine, but MG2 also can act as a generator, for instance, during deceleration for regenerative braking. [28] [30]

Schematically, MG1 is connected to the central sun gear (S), the internal combustion engine is connected to the planetary gear carrier (P) and not to any individual gear, and MG2 is connected to the ring gear (R). The wheels are connected to the ring gear through appropriate reduction gearing and a differential, not illustrated in the diagram. [28]

The Toyota Hybrid System uses a high-voltage battery pack, ranging between 276 and 288 V. There has been a continuous, gradual improvement in the specific capacity of the traction battery. The original Prius used shrink-wrapped 1.2 volt D cells, and all subsequent THS/HSD vehicles have used custom 7.2 V battery modules mounted in a carrier.

G1 single-motor

Schematic diagram of single-motor THS transaxle (P210) with v-belt CVT G01 Toyota Hybrid System (CVT).svg
Schematic diagram of single-motor THS transaxle (P210) with v-belt CVT

In 2001, a modified version of the Generation 1 THS transaxle was released in the Japanese domestic market as the P210 transaxle, fitted to the Estima minivan. [29] The P210 couples the internal combustion engine with the sun gear and couples the starter/generator (MG1) with the planetary gear carrier, which is the opposite of the G1 THS scheme. In addition, the single-motor G1 THS omits the traction motor (MG2) and uses a belt-drive continuously variable transmission which can be selectively coupled via rotating clutches to either the planetary gear carrier or the ring gear.

An all-wheel drive option for the Estima was released at the same time; the Q410 rear drive unit uses an electric traction motor with no mechanical coupling to the front transaxle. [29]

Generation 2 (Toyota Hybrid System-II)

THS was followed by THS-II in the 2004 Prius. Starting with THS-II, Toyota also began referring to the system as Hybrid Synergy Drive (HSD). Compared to THS, THS-II offered reduced consumption and better performance with increased power and torque. [31] : 21  THS-II uses the same design as THS, combining traction power from an internal combustion engine and an electric motor via a planetary gearset (power split device) which can divert some power to an electrical generator. [32] : 4 

Electrically, HSD/THS-II adds a DC to DC converter boosting the potential of the battery to 500 V or more. This allows smaller battery packs to be used, and more powerful motors. [31] Compared to THS, the physical size of the traction motor (MG2) in THS-II remains approximately the same, but the maximum output has increased from 33 to 50 kW (44 to 67 hp) and the maximum torque has increased from 350 to 400 N⋅m (260 to 300 lbf⋅ft). The stator windings are connected in series, which requires a higher potential. [33]

Although not part of the THS/HSD as such, starting with the 2004 Prius, all THS/HSD vehicles have been fitted with an electric air-conditioning compressor, instead of the conventional engine-driven type. This removes the need to continuously run the engine when cabin cooling is required. Two positive temperature coefficient heaters are fitted in the heater core to supplement the heat provided by the engine. [34]

Generation 3 (Hybrid Synergy Drive)

Schematic diagram of the Third-Generation Hybrid Synergy Drive transaxle (P31x/ P410/ P510); a second planetary gearset has been added G03 Toyota Hybrid System.svg
Schematic diagram of the Third-Generation Hybrid Synergy Drive transaxle (P31x/ P410/ P510); a second planetary gearset has been added

The updated version of HSD first delivered in the model year 2006 RX 400h is similar to THS/THS-II, with the addition of a second planetary gearset, which Toyota calls the Motor Speed Reduction Device (MSRD); it is compounded with the first planetary gearset (PSD) by coupling the two ring gears together. [35] The coupled ring gears are still used to drive the front wheels of the vehicle. The traction motor (MG2) uses the MSRD as a reduction gear, making it possible to increase the power density of the motor. [1] Ford has also developed a similar hybrid system, introduced in the Ford Escape Hybrid.

Toyota CEO Katsuaki Watanabe said in a February 16, 2007 interview that Toyota was "aiming at reducing, by half, both the size and cost of the third-generation HSD system". [36] The new system will feature lithium-ion batteries in later years. Lithium-ion batteries have a higher energy capacity-to-weight ratio compared to NiMH, but operate at higher temperatures, and are subject to thermal instability if not properly manufactured and controlled, raising safety concerns. [37] [38]

G3 all-wheel drive with hybrid transaxle

In 2005, vehicles such as the Lexus RX 400h and Toyota Highlander Hybrid added four-wheel drive operation by adding a third electric motor ("MGR") on the rear axle. In this system, the rear axle is purely electrically powered, and there is no mechanical link between the engine and the rear wheels. This also permits regenerative braking on the rear wheels.

G3 rear-wheel drive (Lexus Hybrid Drive)

Schematic diagram of rear-wheel Lexus Hybrid Drive transmission (L110/ L110F) G03 Toyota Hybrid System (RWD).svg
Schematic diagram of rear-wheel Lexus Hybrid Drive transmission (L110/ L110F)

In 2006 and 2007, a further development of the HSD drivetrain, under the Lexus Hybrid Drive name, was fitted to the Lexus GS 450h / LS 600h sedans as the L110 transmission. Previous versions of HSD/THS were fitted to transaxles used with front-wheel drive platforms; Lexus Hybrid Drive applied the two-motor HSD concept to a longitudinal transmission for rear-wheel drive vehicles. This system uses two clutches (or brakes) to switch the second motor's gear ratio to the wheels between a ratio of 3.9 and 1.9, for low and high speed driving regimes respectively. This decreases the power flowing from MG1 to MG2 (or vice versa) during higher speeds. The electrical path is only about 70% efficient, thus decreasing its power flow while increasing the overall performance of the transmission. The second planetary gearset is extended with a second carrier and sun gear to a ravigneaux-type gear with four shafts, two of which can be held still alternatively by a brake/clutch.

The GS 450h and LS 600h systems utilized rear-wheel drive and all-wheel drive drivetrains, respectively, and were designed to be more powerful than non-hybrid versions of the same model lines, [2] [3] while providing comparable engine class efficiency. [39]

Schematic diagram of updated rear-wheel Hybrid Synergy Drive transmission (L210/ L210F) G03 Toyota Hybrid System (RWD alt).svg
Schematic diagram of updated rear-wheel Hybrid Synergy Drive transmission (L210/ L210F)

A simplified version was released in 2012 with the fourteenth generation Crown (S210); the L210 transmission omits the two clutches but retains the second planetary gearset (MSRD) applied to the output of MG2, in common with other Generation 3 transaxles. However, compared to the G3 transaxles, instead of coupling the two ring gears, the L210 couples the PSD ring gear to the MSRD planetary gear carrier, and grounds the ring gear of the MSRD instead of the planetary gear carrier.

Generation 4

Schematic diagram of Fourth-Generation Hybrid Synergy Drive transaxle (P610/ P71x/ P810/ P910) G04 Toyota Hybrid System.svg
Schematic diagram of Fourth-Generation Hybrid Synergy Drive transaxle (P610/ P71x/ P810/ P910)

On October 13, 2015, Toyota announced details of the Fourth Generation Hybrid Synergy Drive which was introduced for the 2016 model year. The overall design returns to a single planetary gearset similar to THS/THS-II; parallel reduction gears on the Fourth Generation transaxles replace the Motor Speed Reduction Device, which is a second planetary gear set found in the Third Generation transaxles. The transaxle and traction motor have been redesigned, delivering a reduction in size and combined weight. [40] The traction motor itself is considerably more compact and gains a better power-to-weight ratio. Notably there is a 20 percent reduction in mechanical losses due to friction compared to the previous model. The 2012– Prius c retains the P510 transaxle. The P610 transaxle employs helical gears rather than the straight-cut spur gears employed in the earlier transaxles, and which run more smoothly and quietly, while also accommodating higher mechanical loads.

G4 all-wheel drive with hybrid transaxle

With the Fourth Generation HSD, Toyota is also offering a four-wheel drive option, dubbed "E-Four", similar to the 2005 RX400h and Highlander Hybrid, in which an electric traction motor is added to the rear, but is not mechanically coupled to the internal combustion engine or front inverter. In fact, the "E-Four" system has its own rear inverter, although this inverter draws power from the same hybrid battery as the front inverter. "E-Four" began being offered in Prius models in the United States in the 2019 model year. "E-Four" is an integral part of the RAV4 Hybrid models offered in the United States, and all such RAV4 Hybrids are "E-Four" only.

G4 rear-wheel drive (Multistage THS-II)

Fourth Generation L310 / L310F Hybrid Synergy Drive transmission for rear-wheel drive vehicles G04 Toyota Hybrid System (RWD alt).svg
Fourth Generation L310 / L310F Hybrid Synergy Drive transmission for rear-wheel drive vehicles

The L310 transmission for rear-wheel drive applications succeeded the prior L110 transmission in premium vehicles. Compared to the L110 and L210, the L310 couples MG2 to the ring gear of the PSD. In addition L310 adds a third planetary gearset, compounded with the second (MSRD) by coupling the planetary gear carrier of the second planetary gearset with the ring gear of the third planetary gearset, and by coupling the ring gear of the second with the planetary gear carrier of the third.

In addition, several rotating clutches and brakes have been added, including a one-way clutch on the planetary gear carrier of the second planetary gearset. By selectively engaging these, the transmission can simulate ten different gear ratios. [40]

Generation 5

The fifth generation Hybrid Synergy Drive transaxle is similar to the prior generation, with detail improvements making the electric motors lighter, more compact, and more powerful. [41]

List of vehicles with HSD technology

The following is a list of vehicles with Hybrid Synergy Drive and related technologies (Toyota Hybrid System):

Patent issues

Antonov

As of autumn 2005, the Antonov Automotive Technology BV Plc company has sued Toyota, the Lexus brand mother company, over alleged patent infringement relating to key components in the RX 400h's drivetrain and the Toyota Prius hybrid compact car. The case has been pending in secret since April 2005, but settlement negotiations did not bring a mutually acceptable result. Antonov eventually took legal recourse in the German court system, where decisions are usually made relatively swiftly. The patent holder seeks to impose a levy on each vehicle sold, which could make the hybrid SUV less competitive. Toyota fought back by seeking to officially invalidate Antonov's relevant patents. The court motion in Microsoft Word document format can be read here. [46]

On 1 September 2006 Antonov announced that the Federal Patent Court in Munich has not upheld the validity of the German part of Antonov's patent (EP0414782) against Toyota. A few days later, a court in Düsseldorf had ruled that the Toyota Prius driveline and the Lexus RX 400h driveline do not breach the Antonov hybrid CVT patent. [47]

Ford

Ford Motor Company independently developed a system with key technologies similar to Toyota's HSD technology in 2004. As a result, Ford licensed 21 patents from Toyota in exchange for patents relating to emissions technology. [48]

Paice

Paice LLC received a patent for an improved hybrid vehicle with a controllable torque transfer unit ( USpatent 5343970,Severinsky; Alex J.,"Hybrid electric vehicle",issued 1994-09-06 ) and has additional patents related to hybrid vehicles. In 2010 Toyota agreed to license Paice's patents; terms of the settlement were not disclosed. [49] In the settlement "The parties agree that, although certain Toyota vehicles have been found to be equivalent to a Paice patent, Toyota invented, designed and developed the Prius and Toyota’s hybrid technology independent of any inventions of Dr. Severinsky and Paice as part of Toyota’s long history of innovation". [50] Paice earlier entered into an agreement with Ford for the license of Paice's patent. [51]

Comparison with other hybrids

Aisin Seiki Co., minority-owned by Toyota, supplies its versions of the HSD transmission system to Ford for use as the "Powersplit" e-CVT in the Ford Escape hybrid [52] and Ford Fusion Hybrid. [53]

Nissan licensed Toyota's HSD for use in the Nissan Altima hybrid, using the same Aisin Seiki T110 transaxle as in the Toyota Camry Hybrid.[ citation needed ] The 2011 Infiniti M35h uses a different system of one electric motor and two clutches.

In 2010, Toyota and Mazda announced a supply agreement for the hybrid technology used in Toyota's Prius model. [54]

General Motors, DaimlerChrysler's and BMW's Global Hybrid Cooperation is similar in that it combines the power from a single engine and two motors. In 2009, the Presidential Task Force on the Auto Industry said that "GM is at least one generation behind Toyota on advanced, 'green' powertrain development". [55]

In contrast, Honda's Integrated Motor Assist uses a more traditional ICE and transmission where the flywheel is replaced with an electric motor, thereby retaining the complexity of a traditional transmission.

Aftermarket

Some early non-production plug-in hybrid electric vehicle conversions have been based on the version of HSD found in the 2004 and 2005 model year Prius. Early lead-acid battery conversions by CalCars have demonstrated 10 miles (16 km) of ev-only and 20 miles (32 km) of double mileage mixed-mode range. A company planning to offer conversions to consumers named EDrive systems will be using Valence Li-ion batteries and have 35 miles (56 km) of electric range. Both of these systems leave the existing HSD system mostly unchanged and could be similarly applied to other hybrid powertrain flavors by simply replacing the stock NiMH batteries with a higher capacity battery pack and a charger to refill them for about $0.03 per mile from standard household outlets.

See also

Related Research Articles

<span class="mw-page-title-main">Hybrid vehicle</span> Vehicle using two or more power sources

A hybrid vehicle is one that uses two or more distinct types of power, such as submarines that use diesel when surfaced and batteries when submerged. Other means to store energy include pressurized fluid in hydraulic hybrids.

<span class="mw-page-title-main">Automatic transmission</span> Type of motor vehicle transmission that automatically changes gear ratio as the vehicle moves

An automatic transmission is a multi-speed transmission used in motor vehicles that does not require any input from the driver to change forward gears under normal driving conditions. Vehicles with internal combustion engines, unlike electric vehicles, require the engine to operate in a narrow range of rates of rotation, requiring a gearbox, operated manually or automatically, to drive the wheels over a wide range of speeds.

<span class="mw-page-title-main">Four-wheel drive</span> Type of drivetrain with four driven wheels

A four-wheel drive, also called 4×4 or 4WD, is a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case providing an additional output drive shaft and, in many instances, additional gear ranges.

<span class="mw-page-title-main">Honda Insight</span> Motor vehicle

The Honda Insight is a hybrid electric vehicle that is manufactured and marketed by Honda. Its first generation was a two-door, two passenger liftback (1999–2006) and in its second generation was a four-door, five passenger liftback (2009–2014). In its third generation, it became a four-door sedan (2018–2022). It was Honda's first model with Integrated Motor Assist system and the most fuel efficient gasoline-powered car available in the U.S. without plug-in capability for the length of its production run.

<span class="mw-page-title-main">Engine braking</span> Retarding forces within an engine used to slow a vehicle

Engine braking occurs when the retarding forces within an internal combustion engine are used to slow down a motor vehicle, as opposed to using additional external braking mechanisms such as friction brakes or magnetic brakes.

Global Hybrid Cooperation, formerly Advanced Hybrid System 2 (AHS2), is a set of hybrid vehicle technologies jointly developed by General Motors, Daimler, and Chrysler LLC, with BMW joining in 2005. It uses 2 or 3 planetary gearsets in an automatic transmission: one on the internal combustion engine (ICE) side paired with a second, forming the compound split, and possibly one third additional planetary gearset to multiply the number of fixed gear ratios. General Motors has stopped using the "AHS2" name as of 2006, preferring to call it simply a two-mode hybrid system.

Toyota Motor Corporation's U family is a family of automatic front-wheel drive/rear-wheel drive/four-wheel drive transmissions found in later vehicle models.

BAS is a category of automotive parallel hybrid technology that uses an electric motor to contribute power to the internal combustion engine's crankshaft via a serpentine belt. By mounting this motor generator unit in the conventional location traditionally used for the standard automotive alternator, it permits a low-cost method of adding mild hybrid capabilities such as start-stop, power assist, and mild levels of regenerative braking. BAS systems differ from other mild hybrid systems as they are not run off the vehicle's crankshaft.

Hybrid vehicle drivetrains transmit power to the driving wheels for hybrid vehicles. A hybrid vehicle has multiple forms of motive power, and can come in many configurations. For example, a hybrid may receive its energy by burning gasoline, but switch between an electric motor and a combustion engine.

<span class="mw-page-title-main">Hybrid electric vehicle</span> Type of hybrid vehicle and electric vehicle

A hybrid electric vehicle (HEV) is a type of hybrid vehicle that combines a conventional internal combustion engine (ICE) system with an electric propulsion system. The presence of the electric powertrain is intended to achieve either better fuel economy than a conventional vehicle or better performance. There is a variety of HEV types and the degree to which each functions as an electric vehicle (EV) also varies. The most common form of HEV is the hybrid electric car, although hybrid electric trucks, buses, boats, and aircraft also exist.

Voltec, formerly known as E-Flex, is a General Motors powertrain released in November 2010. The Voltec architecture is primarily a plug-in capable, battery-dominant electric vehicle with additional fossil fuel powered series and parallel hybrid capabilities.

<span class="mw-page-title-main">Toyota Sai</span> Motor vehicle

The Toyota Sai is a hybrid electric car sharing the same platform and hybrid drivetrain as the Lexus HS. It was launched in Japan on October 20, 2009, following the launch of the Lexus HS in January of the same year. Toyota received about 14,000 orders in one month after its introduction, and the Sai is available at all Toyota Japanese dealership sales channels.

<span class="mw-page-title-main">Toyota Prius (XW30)</span> Motor vehicle

The third generation Toyota Prius debuted as a compact liftback manufactured and marketed by Toyota, having launched in 2009 for model year 2010 at the January 2009 North American International Auto Show. Internally designated as model XW30 and replacing the XW20 series, sales began in Japan on May 18, 2009.

<span class="mw-page-title-main">Toyota Prius C</span> Motor vehicle

The Toyota Prius c (c stands for "city"), also known as the Toyota Aqua (Japanese: トヨタ・アクア, Hepburn: Toyota Akua); "aqua" is Latin for water) in Japan, is a full hybrid gasoline-electric subcompact/supermini hatchback manufactured and marketed by Toyota. The Prius c is the third member of the Prius family, and combines the features of a Yaris-sized car with a hybrid powertrain. The Prius c is priced lower than the conventional Prius and has a higher fuel economy in city driving under United States Environmental Protection Agency test cycles. The Prius c was ranked by the EPA as the 2012 most fuel efficient compact car when plug-in electric vehicles are excluded.

<span class="mw-page-title-main">Drivetrain</span> Group of components that deliver power to the driving wheels

A drivetrain or transmission system, is the group of components that deliver mechanical power from the prime mover to the driven components. In automotive engineering, the drivetrain is the components of a motor vehicle that deliver power to the drive wheels. This excludes the engine or motor that generates the power. In marine applications, the drive shaft will drive a propeller, thruster, or waterjet rather than a drive axle, while the actual engine might be similar to an automotive engine. Other machinery, equipment and vehicles may also use a drivetrain to deliver power from the engine(s) to the driven components.

Petrol–electric transmission or gasoline–electric transmission or gas–electric transmission is a transmission system for vehicles powered by petrol engines. Petrol–electric transmission was used for a variety of applications in road, rail, and marine transport, in the early 20th century. After World War I, it was largely superseded by diesel–electric transmission, a similar transmission system used for diesel engines; but petrol–electric has become popular again in modern hybrid electric vehicles.

E-Four, eFour, AWD-i, or AWD-e was developed by Toyota. Front wheels are powered directly by the hybrid powertrain, rear wheels are powered by a dedicated electric motor with its own power control unit, reduction gear and differential. Amount of torque transferred to the rear wheels is automatically adjusted by the vehicle's electronic control unit according to driving conditions. E-Four also adds additional regenerative braking. In North America, Toyota uses the term AWD-i. There is no drive shaft between the front combustion engine and rear wheels. The rear wheels only receive power and torque from the rear electric motor(s).

<span class="mw-page-title-main">Lexus LC</span> Motor vehicle

The Lexus LC is a grand tourer manufactured by Lexus, a luxury division of Toyota. Based on the 2012 LF-LC Concept, it was revealed at the 2016 North American International Auto Show in Detroit. It replaced the SC, which was produced from 1991 to 2010. The LC is the first Lexus model to utilize the GA-L platform, which, along with other components, is shared with the full-size XF50 series LS sedan. According to Lexus, the name "LC" stands for "Luxury Coupe".

Toyota Motor Corporation's L-series of HybridSynergyDrive (HSD) transmissions are hybrid gearboxes containing 2 electric motors, one for driving the wheels and one for controlling the ratio between the engine and the electric drive motor, as well as an optional 2 or 4 speed planetary transmission attached to the end of the HSD device OR a conventional automatic transmission that uses an electric drive motor instead of a torque converter for additional vehicle propulsion.

References

  1. 1 2 Vasilash, Gary (February 2005). "A Lexus Like No Other But Like The Rest:Introducing The RX 400h". Automotive Design and Production. Archived from the original on 2006-10-17. Retrieved 2010-07-12.
  2. 1 2 "Lexus GS450h – Road Tests". CAR Magazine. Archived from the original on 2011-07-26. Retrieved 2010-07-13.
  3. 1 2 Vasilash, Gary (July 2006). "The Lexus LS 600H L: Not Just Another Production Car". Automotive Design and Production. Archived from the original on 2007-06-17. Retrieved 2010-04-12.
  4. ↑ "News Releases > Worldwide Sales of TMC Hybrids Top 2 Million Units". TOYOTA. 2009-09-04. Archived from the original on 2018-03-16. Retrieved 2009-12-03.
  5. 1 2 Toyota Press Room (2013-04-17). "Toyota cumulative global hybrid sales pass 5M, nearly 2M in US". Green Car Congress . Retrieved 2013-04-17.
  6. ↑ John Voelcker (2014-10-03). "Toyota Racks Up 7 Million Hybrids Sold Since 1997". Green Car Reports. Retrieved 2014-10-03.
  7. ↑ All electric motors with excited fields, either by a (separately-excited) electro–magnet rotor or a (integrally-excited) permanent–magnet rotor, can be used as generators (and vice versa), so the term motor–generator is normally used only when the same device is being used for both purposes, although not simultaneously.
  8. ↑ Burress, Timothy Adam (2006). "Vector Control and Experimental Evaluation of Permanent Magnet Synchronous Motors for HEVs" (PDF). University of Tennessee. p. 16. Retrieved 29 September 2012.
  9. ↑ Bill Siuru. "Synergy Drive: Why Toyota's Hybrids Rock". Green Car Journal. Yahoo. Archived from the original on 2009-09-28. Retrieved 2008-03-12.
  10. ↑ In 2007 and later Camrys, this ratio is 2.636, and in 2010 and later Priuses, this ratio is 2.478, for an average ratio of roughly 2.5
  11. 1 2 3 4 Politechnika Wrocławska - Inżynieria Pojazdów. "Case study: Toyota Hybrid Synergy Drive" (PDF). Wrocław University of Technology . Retrieved 2014-11-22.See Auris HSD specs in pp.17: 201.6V x 6.5Amp/hr = 1.310kWh
  12. ↑ The Advanced Lead-Acid Battery Consortium (ALABC). "Do Hybrid Electric Vehicles Use Lead-Acid Batteries? Yes! Here's why". ALABC. Archived from the original on 2014-05-06. Retrieved 2014-11-23.
  13. 1 2 Brad Berman (2008-11-06). "The Hybrid Car Battery: A Definitive Guide - Today's Hybrid Car Battery: Nickel Metal Hydride - Toyota Prius Hybrid Battery". HybridCars.com. Retrieved 2014-11-22.
  14. ↑ Toyota. "Toyota Prius - Three drive modes". Toyota01. Retrieved 2014-11-23.EV Mode works under certain conditions at low speeds for up to a mile.
  15. ↑ Anh T. Huynh (2012-10-15). "2012 Toyota Camry Hybrid XLE: Technology In A Mid-Size Sedan". Tom's Hardware. Retrieved 2014-11-23.
  16. ↑ U. S. Environmental Protection Agency and U.S. Department of Energy (2014-11-21). "Compare Side-by-Side - 2012/2013/2014 Toyota Prius Plug-in Hybrid". Fueleconomy.gov. Retrieved 2014-11-21.
  17. ↑ "2010 Prius Plug-in Hybrid Makes North American Debut at Los Angeles Auto Show; First Li-ion Battery Traction Battery Developed by Toyota and PEVE". Green Car Congress. 2009-12-02. Retrieved 2010-02-03.
  18. 1 2 "Toyota Introduces 2012 Prius Plug-in Hybrid" (Press release). Toyota. 2011-09-16. Archived from the original on 2014-10-14. Retrieved 2014-11-21.
  19. 1 2 Josh Pihl (January 2014). "Table 33. Batteries for Selected Hybrid-Electric Vehicles, Model Years 2013-2014". Oak Ridge National Laboratory. Archived from the original on 2014-11-29. Retrieved 2014-11-21.
  20. ↑ Based on Min a Max values from Hybrid Assistant App (High Voltage Battery Statistics)
  21. ↑ Based on Min a Max values from Hybrid Assistant App (High Voltage Battery Statistics)
  22. ↑ Wayne Cunningham (2014-11-19). "Toyota Mirai: The 300-mile zero-emission vehicle". CNET . Retrieved 2014-11-21.The Mirai has a 245-volt nickel-metal hydride battery pack, similar to that in the Camry Hybrid. 245V x 6.5Amp/hr = 1.59kWh
  23. ↑ Toyota. "Yaris & Yaris HSD brochure" (PDF). Toyota South Africa. Retrieved 2014-11-22.See specs table: 144V x 6.5Amp/hr = 0.936kWh
  24. ↑ Camry Hybrid 2012 owner's manual [ permanent dead link ]
  25. ↑ DeBord, Matthew (2016-05-06). "This feature of the Toyota Prius is a complete mystery to most owners". Business Insider.
  26. ↑ Toyota 2007 Prius Owner's Manual (OM47568U) (PDF). p. 146.
  27. ↑ "Toyota Hybrid - Transmissions line-up". Toyota-Club.net. June 2024. Retrieved 13 September 2024.
  28. 1 2 3 4 "Toyota Introduces New Passenger Vehicle Hybrid System" (Press release). Toyota Motor Corporation. March 25, 1997. Retrieved 11 September 2024.
  29. 1 2 3 "Technical Development: Drivetrain". Toyota Motor Corporation. Retrieved 13 September 2024.
  30. ↑ "The Story Behind the Birth of the Prius, Part 1". Toyota Motor Corporation. December 11, 2017. Retrieved 11 September 2024.
  31. 1 2 "Toyota Hybrid System THS II" (PDF). Toyota Motor Corporation. May 2003. Retrieved 11 September 2024.
  32. ↑ Staunton, R. H.; Ayers, C. W.; Marlino, L. D.; Chiasson, J. N.; Burress, T. A. (May 2006). Evaluation of 2004 Toyota Prius Hybrid Electric Drive System (ORNL/TM-2006/423) (PDF) (Report). Oak Ridge National Laboratory. Retrieved 11 September 2024.
  33. ↑ Hsu, J. S.; Ayers, C. W.; Coomer, C. L. (July 2004). Report on Toyota/Prius motor design and manufacturing assessment (ORNL/TM-2004/137) (PDF) (Report). Oak Ridge National Laboratory. Retrieved 13 September 2024.
  34. ↑ "6 – Body Electrical". Toyota Hybrid System – Course 071 (PDF). Toyota Technical Training. p. 1. Archived from the original (PDF) on 2008-10-31. Retrieved 2008-10-15.
  35. ↑ Burress, T. A.; Campbell, S. L.; Coomer, C. L.; Ayers, C. W.; Wereszczak, A. A.; Cunningham, J. P.; Marlino, L. D.; Seiber, L. E.; Lin, H. T. (March 2011). Evaluation of the 2010 Toyota Prius Hybrid Synergy Drive System (ORNL/TM-2010/253) (PDF) (Report). Oak Ridge National Laboratory. Retrieved 11 September 2024.
  36. ↑ "Toyota's Bid for a Better Battery". Archived from the original on 2007-02-28.
  37. ↑ Halvorson, Bengt. Li-ion Not Ready for Prius Archived 2007-06-20 at the Wayback Machine . BusinessWeek, June 18, 2007. Retrieved on 2007-08-07.
  38. ↑ "DailyTech – Toyota Shuns Lithium-ion Batteries for Next Gen Prius". Archived from the original on 2011-05-18. Retrieved 2010-12-19.
  39. ↑ "2008 Lexus LS 600h L Overview". Vehix.com. Archived from the original on 2011-07-17. Retrieved 2010-07-13.
  40. 1 2 "Advancement of Toyota Hybrid System II (THS-II)". Toyota Motor Corporation. December 6, 2016. Retrieved 11 September 2024.
  41. ↑ "Toyota starts production of 5th generation hybrid powertrain" (Press release). Toyota Motor Corporation Europe. December 19, 2022. Retrieved 14 September 2024.
  42. ↑ "Nissan Discontinues Altima Hybrid". 14 June 2011.
  43. ↑ "2019 Subaru Crosstrek Hybrid". Subaru. Retrieved 24 November 2018.
  44. ↑ "All-New Subaru Crosstrek Hybrid To Debut At Los Angeles Auto Show" (Press release). PR Newswire. Retrieved 24 November 2018.
  45. ↑ "2019 Subaru Crosstrek Hybrid: First drive of 17-mile, 35-mpg plug-in crossover". Green Car Reports. 19 November 2018. Retrieved 24 November 2018.
  46. ↑ "Toyota infringement of Antonov hybrid technology patents alleged". 19 September 2005.
  47. ↑ "Düsseldorfer Archiv". www.duesseldorfer-archiv.de. Retrieved 6 April 2018.
  48. ↑ Bruce Nussbaum (2005-11-01). "Is Ford Innovative? Part Two". Bloomberg Businessweek. Archived from the original on February 22, 2006. Retrieved 2011-03-09.
  49. ↑ Joann Muller (2010-07-19). "Toyota Settles Hybrid Patent Case". Forbes.com . Archived from the original on 2013-01-23. Retrieved 2011-03-09.
  50. ↑ "Toyota and Paice reach settlement of patent disputes" (Press release). Paice LLC. 2010-07-09. Retrieved 2011-03-09.
  51. ↑ "Paice and Ford Reach Settlement in Hybrid Vehicle Patent Infringement Disputes" (Press release). Paice LLC via PR Newswire. 2010-07-16. Retrieved 2011-03-09.
  52. ↑ "AISIN at a Glance" (PDF). Aisin Seiki Co. 2005-09-21. Archived from the original (PDF) on 2010-12-12. Retrieved 2011-03-09. Developed the HD-10 proprietary hybrid drive "dual system" for use in the Ford Escape Hybrid
  53. ↑ "Ford Fleet – Showroom – Cars – 2010 Fusion Hybrid". Ford Motor Company . Retrieved 2011-03-09.
  54. ↑ "TMC and Mazda Agree to Hybrid System Technology License" (PDF) (Press release). Toyota & Mazda. 2010-03-29. Retrieved 2010-03-29.
  55. ↑ "Determination of Viability Summary: General Motors Corporation" (PDF). 2009-03-30. Archived from the original (PDF) on 2009-04-07. Retrieved 2009-12-03.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.