Cordless hand drill

Makita 18v electric drill

A cordless drill ^[1] or battery drill is a portable power tool that operates on rechargeable batteries, usually lithium-ion technology. Its cordless design allows great freedom of movement, making it ideal for DIY, carpentry, assembly and professional use on construction sites. ^[2]

Features

From a technical point of view, this type of tool is powered exclusively by energy from the integrated battery, which determines both its power and its working autonomy. It is designed to perform basic functions such as drilling materials and screwdriving, and in some cases, it can also incorporate a hammering action, useful for working on masonry surfaces. The drill bit clamping system is usually made up of automatic drill chucks, although there are variants with a traditional key. One of the aspects most valued by users is the possibility of regulating the torque by means of different pre-set levels, which allows the force of the motor to be adapted to the demands of the material or the task. They usually incorporate an LED light, charge indicator and carrying case.

Type according voltage

Cordless drills are usually categorized by the voltage of the pack that powers their motor, as this determines its power, autonomy and practical application. The 10 to 12 volt models are mainly aimed at household chores, light assemblies or precision work. Relevant examples in this category include the Bosch PS31, the Bosch GSR 12V-15, the Makita DF331DSAE, and the Black+Decker BDCHD12S1. They are compact, ergonomic drills with sufficient performance for occasional uses.

In the intermediate segment, 14.4V drills offer a good balance between size and strength. Although this voltage has been displaced by the 18 V standard in many current ranges, there are still current models such as the Bosch GSR 1440-LI, the Makita HP347D and the DF347DWE, which also work with compatible batteries such as the Makita BL1430B.

The 18 to 21 volt drills make up the most widespread professional range. Designed for demanding tasks, drilling in hard materials and intensive use, models such as the Bosch GSR 1800-LI, the GSB 18V-21, the Makita DHP453RFE, the DeWalt DCD776C3-QW, the Einhell TE-CD 18 Li-i and the Worx WX375 are widely used both on construction and in renovations and carpentry.

Finally, there are less common 28 V drills that are usually oriented to industrial environments where higher sustained performance is required. Milwaukee and DeWalt offer variants within this category, usually with high-amperage packs.

Technical comparison between models

They started out as low-power electric screwdrivers, but today they fill a very wide range in the market. ^{[3] [4]}

Brand	Model	Volts	Engine	Max. torque	Max RPM	Percussion	Drill chuck	Drilling capacity (Wood / Metal / Bricks)
Bosch	GSB 18V-55	18V	Brushless	55 Nm	1,800	Yes	13 mm	35mm / 13mm / 13mm
Bosch	GSR 18V-110 C	18V	Brushless	110 Nm	2,100	No	13 mm	82mm / 13mm / —
Bosch	GSR 1800-LI	18V	With brushes	34 Nm	1,300	No	10mm	29mm / 10mm / —
Bosch	PS31	12V	With brushes	30 Nm	1,300	No	10mm	19mm / 10mm / —
Makita	DHP453RFE	18V	With brushes	42 Nm	1,300	Yes	13 mm	36mm / 13mm / 13mm
Makita	DF331DSAE	12V	With brushes	30 Nm	1,700	No	10mm	21mm / 10mm / —
Makita	HP347D	14.4V	With brushes	34 Nm	1,400	Yes	10mm	25mm / 10mm / 10mm
DeWalt	DCD796D2	18V	Brushless	70 Nm	2,000	Yes	13 mm	38mm / 13mm / 13mm
DeWalt	DCD710D2	10.8V	With brushes	24 Nm	1,500	No	10mm	20mm / 10mm / —
Einhell	TE-CD 18 Li-i	18V	Brushless	60 Nm	1,800	Yes	13 mm	38mm / 13mm / 13mm
Worx	WX375	20V	Brushless	60 Nm	1,600	Yes	13 mm	40mm / 13mm / 13mm

Battery pack technology

Battery packs require battery balancing, which is a technique that maximizes a battery's ability to have all of its energy available for use and increases battery longevity. ^[5] The battery regulator is typically a device built into the battery pack that performs battery balancing. ^[6] Most modern cordless drills use lithium-ion batteries that offer: ^[7]

• Greater energy density.
• Less weight.
• Absence of memory defect.
• Fast charging and extended battery life.

Manufacturer	Model	Voltage	Capacity (Ah)	BMS type	Observations
Bosch	PBA 12V 2.5Ah	12V	2.5	External	Home use, Power for All system
Bosch	GBA 18V 5.0Ah	18V	5.0	Internal	Professional, CoolPack technology
Bosch	ProCORE 18V 8.0Ah	18V	8.0	Internal	High energy density, intelligent BMS
Makita	BL1021B	12V	2.0	External	CXT series, compact
Makita	BL1850B	18V	5.0	Internal	LXT series, with load indicator
Makita	BL4040	40V	4.0	Internal	XGT series, digital battery-machine communication
DeWalt	DCB124	12V	3.0	External	XR Compact, light professional use
DeWalt	DCB184	18V	5.0	Internal	XR Li-Ion, compatible with the entire 18V range
DeWalt	DCB546	18V / 54V	6.0	Internal	FLEXVOLT, dual voltage, smart BMS

Internal architecture of battery packs

The nominal voltage of a battery pack is determined by the number of 3.7V cell subgroups connected in series. Each subgroup can consist of one or more cells in parallel, which increases the capacity (Ah) of the pack. ^[8]

Structural typology according to voltage

Rated voltage	No. of 3.7V subgroups in series	Example of models	BMS	Comment
3.7V	1	USB Power Banks	Not required	The cells are in parallel; a 3.7 V → 5 V DC-DC converter is used
10.8–12V	3	Black+Decker BL1510, Makita BL1013, Bosch BAT411 (PS31)	External	2 intermediate sockets for BMS on the charger
14.4–16V	4	Makita BL1415G	External	3 intermediate sockets; BMS usually in the charger
18–21 V	5	Makita BL1850B, Bosch SM31 (GSR 1800-LI)	Internal	4 intermediate sockets; with integrated BMS

The presence of intermediate taps in the pack connector allows the BMS (internal or located in the charger) to monitor and balance the state of charge of each group of cells. This balance is essential in series configurations, since the cells do not automatically balance as they do in parallel. Some low-cost designs use diodes to limit the imbalance between cells, although this technique offers limited protection and can reduce the useful life of the set. ^[9]

Power packs => % charge vs. volts

Loading	3.7V pack	10.1 V pack	14.8V pack	18V pack	21 V-pack
100%	4.2V	12.6V	16.8V	21.0V	25.2V
75%	3.9V	11.7V	15.6V	19.5V	23.1V
50%	3.7V	10.8V	14.4V	18.0V	21.0V
25%	3.5V	10.0V	13.2V	16.5V	18.9V

Applications

In terms of practical applications, cordless drilling machines are widely used for the assembly of furniture, the installation of shelves, curtains or various supports, as well as the drilling of surfaces such as wood, metal and plastic. When it comes to models equipped with a percussion function, the working capacity is extended to harder materials such as brick and lightweight concrete. They are also used for repetitive series screwdriving tasks, especially in industrial processes or chain assembly.

Security

Safety and ergonomics are priority elements in the modern design of these tools. Many models feature grips coated with non-slip material that offer a better grip and reduce fatigue during prolonged use. In addition, electronic protection systems are integrated to prevent overloading and overheating of the motor. Some more advanced versions incorporate electronic brakes, which instantly stop rotation when the trigger is released, increasing safety and control over the tool. The presence of built-in LED lighting is also common, designed to facilitate work in dark areas or with reduced visibility.

See also

• Cordless angle grinder

References

1. "Optimot. Consultes lingüístiques". Llengua catalana (in Catalan). Retrieved 2025-07-30.
2. Klenck, Thomas (March 1989). "Anywhere Drills". Popular Mechanics. Retrieved 2025-07-30– via Google Books.
3. Old-House Journal. Active Interest Media, Inc. 2005. Retrieved 2025-07-30.
4. "Taladros a batería: Comparativa BOSCH, MAKITA y DEWALT". Blog Bricovel (in Spanish). 2018-06-10. Retrieved 2025-07-30.
5. Wen, Sihua (2009). "Cell balancing buys extra run time and battery life" (PDF). Analog Applications Journal.
6. "Battery Management and Monitoring Systems BMS". mpoweruk.com. Retrieved 2024-01-12.
7. Diao, Weiping; et al. (2017). "Active battery cell equalization based on residual available energy maximization". Applied Energy. doi:10.1016/j.apenergy.2017.07.137.
8. "Cell Balancing Design Guidelines" (PDF). Microchip Technology Inc. 2002. Retrieved 2025-07-30.
9. "What is Battery Balancing and Does Your System Need It?". Cadence System Analysis. 2022-09-07. Retrieved 2025-07-30.

Bibliography

• Bell, Brian. Farm Machinery. Old Pond Books, 2010-02-12. ISBN   978-1-910456-23-1
• Peterson, Chris. Black & Decker Readymade Home Furniture: Easy Building Projects Made from Off-the-Shelf Items. Cool Springs Press, 2018-12-25. ISBN   978-0-7603-6162-7

External links

• Salazar, Maria Angeles (2022-06-27). "Nickel, Tesla et deux décennies d'activisme environnemental : Q&R avec le dirigeant Raphaël Mapou". Nouvelles de l'environnement. Retrieved 2025-07-30.