Building Better Batteries
September 24th, 2013
The last major step forward in rechargeable batteries occurred in the early 1990s, when the first lithium-ion cells were introduced. Since then, engineers have gone to great lengths to find ways of powering new mobile features—touchscreens, video cameras, ultra-bright displays—using roughly the same amount of juice.
According to Jeff Dahn, a battery researcher and professor at Dal, a further threefold improvement is probably the best researchers can hope for. “Now, some people wouldn’t consider that a quantum leap, but in batteries, it is,” Dahn says. “Even 25 per cent is a big deal in the battery business.”
Dahn believes there’s a way to make lithium-ion battery cells more powerful by charging them beyond their current 4.2-V maximum. “Many of the positive electrodes can still have a lot of lithium in them at 4.2 V, so if you can charge them to 4.7 V, they will give you about 50 per cent more capacity and energy,” he says.