Zinc air battery to boost power density

Jon Eager, Energizer's director of OEM marketing, said: "We have been working with our OEM partners to refine this battery technology for use in a variety of portable consumer electronic devices and are planning a retail market launch in the summer of 2010." Eager says zinc air technology can provide up to three times the run time of competing technologies. The reason lies in the construction of a zinc air cell. An alkaline cell has quite a thick cathode in comparison to the anode. The zinc air cell, by contrast, needs only a thin membrane. "That means there is twice as much anode and this, along with other efficiencies, provides the increased run time compared with a battery of similar volume." Energizer plans to start manufacturing the PP355 this year. The 1.4V device will measure 32.2 x 14.7 x 5mm – similar in thickness to Li ion prismatics. A further two devices are planned. Energizer believes primary batteries may be more suitable for some applications than rechargeables. "It all depends on the application and how the device is used, but primary batteries can make more sense." One issue which Energizer is working with OEMs to solve is air management. As the power needed from a battery increases, the amount of air supplied must increase proportionally. In the format being developed, a range of air access holes is included on the battery's larger face. In some applications, a tab can be removed from these holes enabling the battery. "But exposure to the environment degrades performance and, once the tab comes off, the battery will typically last a month or so," Eager noted. However, Energizer is considering two further approaches. One is to control air flow by placing an engineered foam against the air access holes. The other is a valve management system. "This could be electronically controlled or use a slide switch," Eager said.