Panasonics 12V Ni-MH used in new idle-stop minicars from Nissan and Mitsubishi

Panasonic Corporation’s NiMH 12V Energy Recovery Systems is being applied in the new idle-stop (stop-start) minicars just introduced by Nissan Motor and Mitsubishi Motors in Japan: the Nissan DAYZ ROOX and Mitsubishi eK Space. The new models were designed and developed for the Japanese market by NMKV Co., Ltd., a joint venture formed by the two automakers.


Panasonic 12V

Panasonic Corporation has developed a NiMH-based 12V Energy Recovery System for start-stop systems in vehicles. This system allows the energy generated during braking to be stored in the batteries and use the stored energy to power the vehicle’s electrical components, thus ensuring power availability even when the engine is not being used. The system is also designed to supply power to the drive assist motor, improving fuel economy.


The 12V Energy Recovery System, which is designed to be connected in parallel with the main lead-acid battery, is based on new D-size nickel metal hydride (NiMH) battery cells. The main lead-acid battery is often placed in the engine compartment. As the new energy recovery system can be installed in the same compartment, it is possible to reduce cable connection resistance and simplify wiring.

To enable such a setup, Panasonic developed battery cells that can endure the high-temperatures of the engine compartment. Using technology acquired in developing HEV batteries, Panasonic has improved the battery design, such as the polar plates, electrolyte and other battery parts to increase charging efficiency and improve durability in high temperature environments.

The system has the same 12V voltage as the main lead-acid battery; as a result, the system eliminates the need for voltage transformation and enables simplification of the control and cooling systems.

The 6Ah, 12V system uses 10 D-size NiMH cells; it measures 230 x 205 x 80mm and weighs approximately 3.4 kg (7.5 lbs).


Permanent link to this article: