Late last week Bosch announced an upgraded Li-ion battery, only the second 18-volt pack to be rated 5.0 Ah or higher; the other is Metabo’s 5.2 Ah pack. Bosch’s BAT621 should be able to store 25% more power than the 4.0 Ah packs that are current top-of-the-line in most cordless systems. The greater storage capacity of this battery will mean longer runtime for any tool it powers. This will be of particular value in power-hungry tools—such as saws, grinders, and rotary hammers—that go through batteries quickly.

The BAT621 pack is the same size and weight as Bosch’s earlier 4.0 and 3.0 Ah packs and can be used in the same tools. Features include a built-in fuel gauge and a heat conductive housing that is said to extend the life of the battery by keeping it cooler.

Available: May 2014
MSRP: $129