In the last two years, a FedEx plane carrying lithium ion batteries has caught fire killing the pilots, a Chinese taxi with passengers caught fire despite the batteries having the potentially safer lithium phosphate cathodes. It is not clear if the battery or BMS are primarily to blame. Laptops caught fire earlier and Sony and Panasonic did recalls. More recently an East Asian lithium-ion battery in a Belgian Post Office bicycle exploded. In each case the incidents raise different issues from how to transport lithium-ion batteries, how to make optimal battery management systems and how to make safer lithium-ion batteries. In the latter respect, Chinese suppliers are notorious for bad quality and dirty factories but some are better than others. However, there have been battery incidents with Chevrolet Volt cars which usually source LGChem batteries from Korea, though exactly what happened is still under investigation. Normally, Sony, Panasonic and LGChem have superb safety records and are among battery "royalty". It is little wonder that some leading automotive manufacturers make their own lithium-ion traction batteries including Toyota, the global leader in electric vehicles by a big margin. Others understand and test battery technology very thoroughly such as BMW, which, following tests, expressed concern about water and oxygen ingress with the pouch construction of the lithium polymer type of traction battery following tests. The term refers to electrolyte that is a solid plus gel instead of a liquid.
It is now urgent for the good manufacturers of lithium-ion traction batteries and their systems in electric vehicles to be distinguished from those encountering problems. Valence Technology seems to be one such manufacturer, with an excellent record of supplying traction batteries for land and water borne electric vehicles. It has recently commented as follows.
Valence Technology recently affirmed the inherent safety of its lithium phosphate chemistry for automotive electric batteries, as demonstrated in cell penetration and cell crush testing.
"Since 2004, Valence Technology has utilized a patented lithium phosphate chemistry in our batteries. This chemistry offers many advantages, including an enhanced safety factor over other lithium chemistries such as lithium metal, lithium metal oxides and lithium mixed metal oxide batteries. While there are dozens of different chemistries under the rechargeable 'lithium ion' umbrella, we firmly believe that our lithium phosphate chemistry offers one of the safest solutions currently available," said Robert L. Kanode, president and chief executive officer of Valence Technology.
Valence is a leading supplier of lithium batteries for the commercial electric fleet market in North America and Europe, and its energy storage solutions are deployed in a host of innovative applications including industrial, marine and health care equipment.
Batteries by their nature are designed to store high energy and thereby can present a risk if that energy is released. Valence employs safety circuitry external of the cell and internal cell safety features to reduce the risk of release of the energy in some situations. However, due to the inherent nature of some cathode materials used in batteries, some risk may be presented which cannot be controlled through the use of safety circuitry and internal cell features. The Underwriters Laboratories (UL) crush test and industry's Japan Storage Battery Association (JSBA) nail penetration test are designed to simulate such additional cell risk factors. Not only does Valence provide safety circuitry external of the cell and internal cell safety features, its cells made with Valence's proprietary cathode materials also pass these crush and nail penetration tests.
For more attend Electric Vehicles Land Sea Air USA 2012,where Mitsubishi Motors (small commercial vehicles and cars), Daimler AG (commercial and military vehicles and cars) will present. Uniquely, a large number of electric vehicle manufacturers not seen in conventional EV events will present including WheelTug airliner electrification on the ground, Pipistrel manned electric aircraft, University of Michigan unmanned solar aircraft, SolTrac electric farm tractors, Monterey Bay Aquarium Research Institute Autonomous Underwater Vehicles AUVs. Many manufacturers of industrial, commercial, military, e-bike, cars and other EVs will be there. At last you can meet those responsible for the majority of the hybrid and pure electric vehicle market and they all need components!! Most are prosperous growing businesses not reliant on government support that can be withdrawn at any time.
