Last week, Panasonic launched production of new, more powerful lithium ion cells at a factory in Japan. The new cells are of the same 18650 format used for laptop batteries and the Tesla Roadster. The new cells have an output of 3.1 Ah at 3.6 volts and energy capacity of 11.2 Wh compared to the previous generation cell's 10.4 Wh. If these cells were used in the Roadster pack (which uses 6,831 cells) it would have a capacity of 76.5 kWh, a 44 percent increase over the the current 53 kWh capacity.
In the press release, Panasonic only discusses supplying these cells for consumer electronics such as laptops and phones. However, earlier this fall there was a report that Panasonic could be providing the cells for the Tesla Model S. Tesla CEO Elon Musk has stated that the company plans to stick with the smaller cell form factor for the Model S rather than using the new larger form factor automotive cells that other companies are adopting. If Tesla does use a variant of these cells for the Model S it would certainly help drive down the cost of the car and improve the range.
Panasonic Starts Mass-Production of High-Capacity 3.1 Ah Lithium-ion Battery
Osaka, Japan - Panasonic Corporation developed a 18650-type high-capacity 3.1 Ah lithium-ion battery and began mass production of the battery this December. The new 3.1 Ah battery has a nickel positive electrode and an energy density of 675 Wh/L. The same type (18 mm in diameter x 65 mm in length) of batteries are widely used in laptop computers.
Demand for lithium-ion batteries is growing as a power source for mobile devices such as laptop computers and mobile phones because their high energy density and light weight properties are suitable for these applications. As such devices become more sophisticated and powerful, they require more robust and safer batteries that do not cause abnormal heating.
The company successfully achieved safety and high capacity by using its unique Heat Resistance Layer (HRL) technology that forms an insulating metal oxide layer between the positive and negative electrodes. The layer prevents the battery from overheating even if a short circuit occurs.
Capitalizing on this technology, Panasonic commercialized a high-capacity 2.9 Ah lithium-ion battery with a nickel positive electrode (energy density: 620 Wh/L) in 2006. Based on the cell construction with the nickel positive electrode and the HRL, the company added improvements to the battery and succeeded in developing the 3.1 Ah lithium-ion battery, the industry's highest capacity in the 18650-type*. The new battery provides long-lasting power to laptops. This high energy density battery can also contribute to downsizing and weight reduction of portable devices. With adoption of the nickel positive electrode, the new rechargeable battery excels in durability in actual use and charge retention - the battery can be stored for a long period of time because of low self-discharge.
Panasonic will continue to refine its battery technology to deliver lithium-ion batteries combining safety with high capacity and use this technology to develop commercially viable green energy storage systems.
*As of December 18, 2009
(New High Capacity Model)
|Capacity||2.9 Ah||3.1 Ah|
|Volume energy density||620 Wh/L||675 Wh/L|
|Diameter||18.6 +0/-0.7 mm||18.6 +0/-0.7 mm|
|Height||65.2 +0/-1.0 mm||65.2 +0/-1.0 mm|
|Mass||Approx. 44 g||Approx. 44.5 g|
|Voltage||3.6 V||3.6 V|
|Charging voltage||4.2 V||4.2 V|
|Energy||10.4 Wh||11.2 Wh|
Panasonic Corporation is a worldwide leader in the development and manufacture of electronic products for a wide range of consumer, business, and industrial needs. Based in Osaka, Japan, the company recorded consolidated net sales of 7.77 trillion yen (US$78.4 billion) for the year ended March 31, 2009. The company's shares are listed on the Tokyo, Osaka, Nagoya and New York (NYSE: PC) stock exchanges. For more information on the company and the Panasonic brand, visit the company's website at http://panasonic.net.