Before lithium-ion batteries, portable gadgets were a nightmare, forcing road warriors and Discman-toting teens to either swap disposable cells or deal with rechargables that (with few exceptions) were tricky to recharge. Of course, Li-ion batteries also have a downside: as laptop and cell phone users have no doubt found out, they too become disposable before long. One reason why is that acid in the electrolyte can corrode the cathode material -- and now, Hitachi claims it's found a way to strengthen its own. Using an undisclosed combination of elements to replace some of the manganese used in the company's cathodes, Hitachi claims they
