Nickel Metal Hydride

The Nickel Metal Hydride battery has a nickel-hydroxide cathode, a metal hydride (a variety of metal alloys are used) anode, and aqueous potassium hydroxide electrolyte. This is a rechargeable battery chemistry that has been superseded by lithium ion, but has seen a lot of use in Toyota hybrids. Energy density 40-110 Wh/kg at cell level.

Toyota Prius Battery

Toyota Prius Gen 2 Battery

This pack was used in the 2004 Toyota Prius. Second generation of the hybrid battery design and using NiMh cells.

This is a HEV pack and so quite a small total energy of 1.3kWh and using a smaller 40% SoC window. This small window is so that the pack will be able to last the lifetime of the car with high charge and discharge rates from braking and acceleration.