Power tool batteries are the driving force behind cordless tools, influencing performance, weight, and runtime. Choosing the right battery type ensures your power tools deliver reliable results. By understanding the differences between battery chemistries (NiCd, NiMH, and Li-ion), you can choose the option that best matches your application.
Power Tool Batteries: Charge Up Your Know-How
Compare NiCd, NiMH, and Li-ion power tool batteries, and learn the essential do’s and don’ts for proper care, charging, and long-lasting performance.
Types of Power Tool Batteries
NiCd (Nickel-Cadmium) Batteries
- Best for: Economical cordless tools and job-site durability.
- Advantages: Fast and simple charging, strong shelf-life, reliable in job-site conditions, and lower cost.
- Limitations: Low energy density, heavier weight at higher voltages, and environmental concerns due to toxic materials.
- Typical Use: 2.4V–18V cordless tools (higher voltages = heavier tools).
- Cycle Life: 500–800 cycles with proper maintenance.
Note: NiCd batteries contain toxic materials and require recycling. Because of these restrictions, many manufacturers are phasing them out in favor of more advanced power tool batteries like NiMH and Li-ion.
NiMH (Nickel-Metal Hydride) Batteries
- Best for: Higher voltage cordless tools up to 19.2V, 24V, and 36V.
- Advantages: Higher energy density than NiCd and more environmentally friendly.
- Limitations: Bulkier and heavier than NiCd, fewer cycles (200–300), and shorter shelf life.
- Performance: Can be compromised in extreme weather, limiting use in some power tool applications.
Li-ion (Lithium-Ion) Batteries
- Best for: Modern power tool batteries that deliver high performance, a lightweight design, and long runtime for today’s cordless tools.
- Advantages: Higher energy per cell for compact, lighter power tools; longer runtime (e.g., a 28V Li-ion pack delivers up to 2x the runtime of an 18V pack); longer life cycle and consistent power output; no self-discharge and environmentally safer (“green”); performs well in extreme weather.
- Safety Features: Require built-in circuit protection to regulate voltage and current. Some manufacturers add extra features such as fuel gauges and overload protection.
- Best Practice: Always use the manufacturer’s recommended battery and charger.
Maintaining & Charging Power Tool Batteries
Proper care and charging habits can significantly extend the life of your power tool batteries. Learn about the do’s and don’ts to keep your batteries performing at their best.
Do’s
Store battery packs in a cool, dry place when not in use.
Recharge NiCd and NiMH packs every 3 months if unused. Li-ion batteries do not require frequent charging.
Allow packs to cool after heavy use before charging to extend life.
Use a charger with maintenance mode for NiCd and NiMH batteries.
Follow the charging and operating temperatures in the manufacturer’s manual.
Don’ts
Do not charge in wet conditions.
Do not tape triggers or leave tools running to discharge batteries. (Li-ion, NiCd, and NiMH do not require full discharge).
Do not leave packs on an unplugged charger, which can slowly drain the battery.
Do not ignore manufacturer-specific recommendations. These general guidelines should always be supplemented with the instructions provided by the tool brand.