Battery capacity reduced to 4.4kWh, EV driving range extended to 26.4km

Toyota launched the Prius PHV (Figure 1), a plug-in hybrid vehicle that can be charged externally, in January 2012. Its feature is that it has a longer driving range as an electric vehicle (EV) than the Prius PHV, which was sold in limited quantities to corporations and government agencies in 2009.

Figure 1: The Prius PHV is aimed at ordinary users. The price starts at 3.2 million yen and only supports ordinary charging.

The original model launched in 2009 was equipped with a 5.2kWh lithium-ion rechargeable battery, and the EV driving range was 23.4km in JC08 mode. The new model has reduced the capacity to 4.4kWh, but has extended the EV driving range to 26.4km. By reducing the battery volume, the floor of the trunk has been lowered compared to the original (Figure 2). The price has been reduced from 5.25 million yen to 3.2 million yen, and the plan is to sell 35,000 to 40,000 units per year.

Figure 2: The trunk floor is lowered
A newly developed small lithium-ion rechargeable battery module was used to lower the trunk floor, ensuring the luggage compartment capacity. The charging port is located on the right side of the rear fender, so the inside is slightly protruding.

The biggest difference between the new model and the previous model is the updated lithium-ion rechargeable battery. It is equipped with a new lithium-ion rechargeable battery with higher capacity and output power, increased regenerative charging, and uses tires with lower rolling resistance. When driving as a hybrid vehicle (HEV), the fuel efficiency in JC08 mode is 31.6km/L. The combined fuel efficiency of plug-in hybrid driving of EV driving and HEV driving is 61.0km/L, which is higher than the previous 57.0km/L.

Figure 3: Units produced by Sanyo Electric
Using units with a capacity of 20.5Ah, 14 units per group, a total of 4 groups. The module weighs 80kg and has a volume of 87L, which is 50% lighter and 57% smaller than before.

Figure 4: Checking the remaining battery power via smartphone
All models are equipped with functions such as displaying the location of charging stations, remotely controlling the air conditioner, and supporting eco-driving.
The original model uses batteries produced by Primearth EV Energy. The battery used in the three-row HEV "Prius α" launched in May 2011 is the same as the battery used in the three-row HEV "Prius α", and the current capacity of the unit is only 5Ah. The positive electrode material is the NCA system using nickel (Ni), aluminum (Al) and cobalt (Co).

The new model uses a large 20.5Ah cell produced by Sanyo Electric (Figure 3). The positive electrode material is based on a ternary system of Ni, Co and manganese (Mn). Compared with the cells used in HEVs, it can not only increase the capacity per unit volume and reduce the cell size, but also increase the amount of charge during regeneration.

The battery module is equipped with 4 groups of 14 cells per group. The battery voltage is 207.2V. By reducing the capacity and changing the outer shell material from steel to aluminum alloy, the weight of the battery module is reduced to 80kg and the volume is reduced to 87L.

Charging only supports normal charging, which takes about 90 minutes with AC200V power supply and about 180 minutes with AC100V power supply to fully charge. It is equipped with a timer function that can charge according to the departure time and use night power to charge. In addition, the new service "PHV Driving Support" that obtains information such as battery remaining power and charging stations through smartphones is standard on all models (Figure 4).