Prius nickel-metal hydride battery and lithium battery both increase output power

Toyota's new Prius boosts the output power of its equipped battery, allowing more current to flow while assisting and charging.

The new Prius uses different batteries depending on the model level. The cheapest "E", upscale models "A" and "A Premium" are equipped with lithium-ion batteries, and the standard "S" and all levels of 4-wheel-drive models are equipped with Ni-MH batteries.

Using two types of batteries requires the same voltage and output power of the battery. The new Prius nickel-metal hydride battery has increased its output power compared to the third-generation Prius. Therefore, lithium-ion batteries have also been redesigned for the products used in the Prius α.

The new nickel-metal hydride battery has a total voltage of 201.6V, a current-carrying capacity of 6.5Ah, and 168 battery cells. The battery module consists of six battery cells. This is the same as the third-generation Prius, but the electrodes are changed, and the power input during charging and the power output during assisted driving are increased. Compared with the original battery, the output power is increased by 28%, and more power can be regenerated when driving on longer downhill road conditions.

In order to match the output power of nickel-hydrogen batteries, lithium-ion batteries also increase output power. The battery used in the Prius α changes the electrode material, while reducing the resistance of the battery cell. The voltage is 207.2V, the current carrying capacity is 3.6Ah, and the number of units is 56.

In addition, the weight of a battery pack including a relay and a battery monitoring unit is 40.3kg for a nickel-metal hydride battery, 1kg less than the original, and the volume is 35.5L, which is 10% less than the original and can be installed under the rear seat. This is achieved by implementing miniaturization of relays, battery monitoring units, and wiring harnesses, and installing the air-cooling fan originally included in the battery pack on the side of the vehicle body. The lithium-ion battery pack weighs 24.5kg and is 15.8kg lighter than the NiMH battery pack.