Product Overview The 400820 is a 3.7V 45mAh lithium-polymer pouch cell manufactured by VATS Battery, an ISO9001-certified lithium battery maker based in Guangdong, China. Built on a compact 3.0×8×20mm (T×W×L) footprint, it combines a stable 3.7V nominal voltage with a true 45mAh capacity, so portable devices run longer on a single charge without adding bulk. Each cell is produced on automated lines and individually screened for capacity, voltage and internal resistance before
