Compared with lithium-ion batteries, the energy density of nickel-hydrogen batteries is not dominant. Take the Ni-MH battery of the third-generation Prius launched by Toyota in 2012 as an example. This Ni-MH battery has a power capacity of only 1.3kWh, but has a weight of 53.3kg and an energy density of only 24.4Wh/kg. The battery capacity can only be supplied. Less than 10 kilometers of pure electric driving. The lithium-ion battery used in the GM VOLT hybrid vehicle launched by GM at the same time has a battery capacity of 16kWh, a weight of 181.4kg, and an energy density of 88.2Wh/kg. The energy density difference between the two is nearly 4 times.
Therefore, if Toyota continues to use nickel-metal hydride batteries, its products can only stay in the mid-hybrid stage to achieve the purpose of reducing fuel consumption in a short time. However, as far as the current global energy development situation is concerned, energy conservation and emission reduction are the goals of the joint efforts of all countries in the world. Pure electric vehicles are one of the mainstream development directions of future automobiles. Toyota wants to get involved in the field of pure electric vehicles, and it must abandon nickel-hydrogen batteries. The route uses a lithium-ion battery with a smaller volume, a lighter weight, and a stronger endurance.
But this does not mean that nickel-metal hydride batteries have a dead end on the road to the development of new energy vehicles. Ni-MH batteries are characterized by high safety, high-power charging and discharging, wide temperature range, environmental friendliness, etc., and the technology is relatively mature. Many companies regard Ni-MH power lithium-ion batteries as a key production research and development project.
Ni-MH battery is the only battery system that has been verified and can be commercialized and scaled among the battery systems currently used in hybrid electric vehicles, and it has a huge share of the hybrid power market. Because it is better than traditional fuel vehicles in terms of environmental friendliness, the hybrid vehicle industry has become one of the strategic emerging industries that the country focuses on fostering. However, due to the high price of nickel-metal hydride batteries, hybrid vehicles using nickel-metal hydride batteries have a much higher price than traditional fuel vehicles. Therefore, only by reducing the cost of the battery and the vehicle can the market advantage be achieved.
The nickel-hydrogen battery industry is in a stage of green development. Like lithium-ion batteries, nickel-metal hydride batteries, as secondary batteries, still have great potential for development in clean energy fields such as new energy vehicles and energy storage.