That fast-charging smartphone you just bought has a dirty secret: more likely than not, it's reducing the lifespan or capacity of the battery to get that breakneck speed. Huawei doesn't think you should have to compromise, though. It just showed off a lithium-ion battery whose graphite-coated anode (where current flows) allows for very quick charging without hurting either capacity or long-term longevity. How quick? With a 3,000mAh of the sort you'd find in a larger phone, Huawei can give you a 48 percent charge in just 5 minutes. Yes, you could have enough power for an evening out in the time it takes to change out of your work clothes. There's an even faster prototype that reaches 68 percent in 2 minutes, although its 600mAh capacity isn't practical at its size.