|Demo vehicle moving into position for battery switch. Click image to see demonstration video.|
Better Place officially opened the Yokohama, Japan EV exhibit with the public debut of its automated battery switch system, designed to make long distance travel by EV convenient for customers.
Better Place selected the Nissan Dualis to demonstrate the battery switch technology. This crossover utility vehicle is not necessarily indicative as to any potential EV lineup by Nissan. The technology demonstration used specially-built 400V battery packs with standard lithium-ion cells from A123Systems. The cells were inserted into an enclosure built to fit this specific Nissan Dualis vehicle application.
|Top view of a fully-charged battery moving up for insertion into the vehicle bay. Click to enlarge.|
The Better Place automated battery switch replaces a depleted EV battery with a fully charged one in just a few minutes, allowing consumers to drive their EVs on long distance trips without actually recharging en route. The technology, which includes the mechanisms for the switch and the control system, is part of an overall solution for EVs that includes an open network of charge spots deployed widely where cars park.
The switch technology was designed and developed by the Better Place Research and Development (R&D) organization, taking advantage of many proven technologies from the automotive and aerospace industries. Better Place is investing significant R&D funding in development of this technology as a core component of the company’s overall infrastructure for EVs.
The switch technology uses an automated track system that runs two robotic battery shuttles. One lowers the depleted battery from the vehicle using a simple hydraulic scissors lift, and then the other inserts the fully charged battery into the vehicle using another lift. The battery shuttles are designed to work with a wide variety of battery enclosure sizes and shapes for universal application to a range of EVs.
The lift platform doesn’t actually touch the car, said Better Place CEO Shai Agassi during the press conference. When releasing a battery, the car and battery separate themselves, and then, when inserting a new battery, the latching mechanism brings the car to the battery and the battery to the car. The battery does not need to be perfectly aligned with the vehicle bay at the beginning of the operation. During this insertion action, the electrical connection is established as well.
The latching mechanism has been tested to 25G, said Agassi.
|The battery pack, with vehicle connector. Click to enlarge.||The vehicle connector. Click to enlarge.|
The switch is controlled by three computers: one onboard the vehicle, one in the station, and one in the battery pack.
The switching process occurs while the driver remains in the vehicle, uses a number of integrated safety systems, and takes less than 80 seconds once the EV is in position.
Since the latching mechanism that secures the battery is based on a common principle used in the aerospace industry, the battery latches are original equipment manufacturer-grade for engineering quality, reliability and durability standards. The switch technology featured in the demonstration will be further developed into production for the commercial battery switch stations that Better Place intends to deploy in markets around the world.
Sharp Corp. provided the solar photovoltaic (PV) power system at the demonstration site in Yokohama. The system provides all the electric power needed to recharge the batteries used in the demonstration via the Better Place charge spots deployed at the site. The PV system helps demonstrate the role renewable energy plays as part of the Better Place solution.
The Yokohama exhibit is part of a six-month feasibility study by the Japanese Ministry of the Environment to increase the adoption of electric vehicles in Japan. Japan wants half of all new vehicles sold in Japan to be electric by 2020.