Two percent of yearly manganese ore production is processed into manganese oxides, which are used in lithium-ion batteries, according to a recent chart from Visual Capitalist. But demand has the potential to grow strongly as more electric cars are built.A recent report from Pike Research pegs global sales of plug-in electric vehicles at 120,000 units in 2012. That's small next to the 62 million total vehicles estimated to have been sold last year, according to a December Scotiabank report. But Pike sees sales of plug-in electrics growing at a combined annualized growth rate of 39 percent between 2012 and 2020. Building a better lithium-ion battery? American Manganese (TSXV:AMY,OTC Pink:AMYZF) recently put out a press release that highlights the differences between lithiated-manganese dioxide batteries and the lithium-cobalt dioxide batteries that Boeing is using. The move was in response to “numerous shareholder queries” about the Boeing 787 situation, according to the release. The company, which aims to develop its Artillery Peak manganese deposit in Arizona, also plans to produce highly pure electrolytic-manganese dioxide (EMD) or chemical-manganese dioxide (CMD) for the battery industry using its proprietary process. The purity of the metal is an often-overlooked part of battery manufacturing, according to Norm Chow, P.Eng., president and CEO of Kemetco Research, who is also quoted in the press release. “A critical issue is that conventional mining processes introduce metallic impurities in raw materials,” said Chow. “These metallic impurities are known to cause internal short circuits resulting in thermal run-away, which bypasses protection circuits implemented for safety. This unfortunately leads to explosions and fires in some cases. The tolerances for these impurities are so low that there are no known methods to reliably test their presence.” Research continues In October 2012, American Manganese successfully built and tested prototype rechargeable batteries using CMD made from Artillery Peak manganese. The small, button-cell batteries were produced using the company's own hydrometallurgical process, which it says produces a highly pure material because it skips steps that have the potential to introduce foreign material.