What is the highest mAh battery?

As of October 2023, the highest capacity consumer batteries typically reach around 20,000 mAh for portable power banks and some specialized lithium-ion battery configurations. There are larger batteries used in electric vehicles and grid storage, which can exceed several hundred amp-hours (Ah), but these are not standard consumer products. For everyday use, power banks with capacities around 20,000 mAh are among the highest available. Always check for the latest advancements, as battery technology is rapidly evolving.