Hitachi starts mass production of 800-volt EV inverter

Hitachi Automotive Systems is starting mass production of its 800-volt, high-output EV inverter. The company says that, thanks to its strong cooling performance, the new inverter delivers twice the voltage and 2.7 times the power density of previous generations.

Most EVs are based on a 400-volt system, so in order to increase driving range, additional batteries with parallel connections are required. This results in increased battery capacity, but also increased charging time. An 800-volt system, however, can charge the battery over a shorter period, allowing for fast charging of high-capacity batteries.

To make the 800-volt system possible, Hitachi developed a compact power module with double-sided cooling and a new high-voltage insulation mounting that dissipates heat. Compared to the previous generation of inverters, the solution delivers twice the voltage at 800 volts and 94.3 kVA/L, which equates to 2.7 times higher power density.

Source: Hitachi

  • ravi teza

    Contrary to popular belief, an 800V system doesnt charge any faster than a 400V system. The net battery capacity is the same in both cases. One doubles the voltage and halves the current capacity to get a similar kWh battery size. The C-Rate in infact half that of a 400V system. However since we doubled the voltage the net charge rate is same as the 400V system. The advantage in an 800V system lies in power density and less copper needed to carry the same current compared to a 400V system.