Batteries and Chargers: Li-ion 3.6–80 V Packs for Cordless Tools

The category includes standalone batteries, standalone chargers and battery-plus-charger starter sets. For household use a 2–4 Ah battery and a standard charger are usually enough, while professional work is better served by 5–8 Ah batteries and fast chargers. See differences between professional and household power tools.

The battery must match the tool voltage (for example 12, 18, 20, 36, 40, 48, 54 or 80 V) and the same manufacturer's platform, since connectors and electronics of different systems are not interchangeable. Before buying, check the platform name and the list of compatible tools. See cordless tool voltage (V) and what is a unified battery platform.

Capacity determines run time per charge: 1.5–2 Ah batteries are light and suit drill drivers, 4–6 Ah suits saws and grinders, and 8–12 Ah suits heavy-duty and garden tools. Higher capacity also adds weight. Read battery capacity (Ah).

Modern batteries use 18650, 21700 or pouch-type Li-ion cells that deliver high current with low self-discharge. A built-in management system protects against overcharging and deep discharge, and an LED gauge shows the remaining charge. Read how to choose batteries, chargers and electronic spare parts for cordless tools.

A standard charger charges a 4 Ah battery in about 1.5–3 hours, while a fast charger does it in 30–60 minutes. Dual-port models charge two batteries in sequence or simultaneously, which is convenient for high workloads.

Quality chargers monitor battery temperature and pause charging when the pack is too hot or too cold, and some models have a fan for faster cooling. Li-ion batteries charge best at around 10–40 °C. See tool safety systems and their purpose.

Use only a compatible charger, do not leave the battery in the sun or in a damp place, and do not use a dropped or damaged pack. For long-term storage, leave about 40–60 % charge and keep it in a cool, dry place. Read how to use cordless tools safely.