Nissan’s LEAF batteries could benefit renewables industry

Nissan is working on a project to give the batteries from the LEAF a second life in the power generation industry.

Nissan believes reused batteries will allow excess power from renewable sources such as solar and wind generation to be stored and then released at peak times, reducing the need for conventional power stations to be kept on standby.

In a statement, the company said a fully charged battery in a LEAF holds enough energy to power a three-bedroom home for around three days (8kW/day). It has potential to store electricity generated by solar and then release it when the sun isn’t shining, or to provide the ability to use wind power even when there is no wind.

‘The Nissan LEAF has only just been launched, but we have to think now about how we will dispose of the car when it comes to the end of its life,’ said Jerry Hardcastle, vice-president of vehicle design and development at Nissan Technical Centre Europe. ‘Although the LEAF is designed to last as long as any conventional car, some batteries will become available from accident-damaged cars sooner and we must manage the use of the parts now.’

The first large-scale demonstration of renewable generation and battery storage using LEAF batteries has been built at Nissan’s global headquarters.

4R Energy, a joint venture established by Nissan and Sumitomo Corporation, has started tests using solar panels and second-life lithium-ion batteries previously used in Nissan LEAFs.

Electricity for the new storage system is generated through solar cells installed at Nissan’s offices, and is stored in the lithium-ion batteries. The power is then used to charge electric vehicles.

With seven charging stations (three quick charge, four normal charge) connected to the solar grid at Nissan’s HQ, the total electricity that can be generated and stored is said to be the equivalent to fully charging approximately 1,800 Nissan LEAFs annually.

Nissan believes this is equivalent to an annual reduction of 15.4 tons of CO2 emissions and will enable electric vehicles to be charged through a completely renewable energy source.

‘Nissan LEAF is already zero emission from a vehicle point of view,’ said Hideaki Watanabe, corporate vice-president for Global Zero Emission at Nissan. ‘Now, in order to maximise that potential, if we utilise the renewable energy on the electricity side, it would really be zero emission.’

Demonstration test outline

Solar cell: Maximum power output: 40kW (Solar Frontier)
Power conditioner: Rated power output: 40kW (10kW× four) (Sanyo Denki)
Storage battery capacity:  96kWh (Automotive Energy Supply Corporation)
Grid management unit: Rated power output: 200kW (Sanyo Denki)
EV charging equipment: Quick charger: three (50kW× three) Regular charger: four (3.3kW×14)