The race is on to develop a longer-lasting rechargeable battery in order to greatly extend the range of electric vehicles, and a team of researchers from Rice University may have found a clue. The researchers have discovered that the charge capacity of lithium-ion batteries could be tripled when the silicon used in them is crushed into a porous powder. The discovery could lead to cheaper, longer-lasting batteries that could help extend the range of EVs.
Silicon can hold about 10 times more lithium ions than the graphite anodes that are currently found in lithium-ion batteries, according to the researchers, but because it swells and shrinks with each charge it tends to break down quickly. So the team decided to try crushing the silicon in order to reduce its volume. The crushed material has more surface area to soak up lithium ions, the team reported.
The paper by researchers Sibani Lisa Biswal and Madhuri Thakur from Rice University in Houston was published this week in Nature.com’s journal Scientific Reports. According to the team, the silicon-based anode achieves 600 charge-discharge cycles at 1,000 milliamp hours per gram (mAh/g) — a serious improvement over the 350 mAh/g capacity of graphite anodes. “That puts it squarely in the realm of next-generation battery technology competing to lower the cost and extend the range of electric vehicles,” said a press release.
Photos by Jeff Fitlow