One of the major limiting factores of rechargeable batteries today is how quickly their capacity can degrade. After just a year of regularly recharging a lithium-ion battery, it can’t get close to its full capacity anymore. However, a new material holds the promise of changing the situation and allowing full capacity charges for five or more years.
As EurekaAlert reports, a team of scientists working at the Japan Advanced Institute of Science and Technology (JAIST) has been looking specifically at the negative terminals inside lithium-ion batteries. They use graphite anodes, but also require a binder material otherwise the graphite would simply fall apart inside the battery.
Today, poly(vinylidene fluoride) (PVDF) is used as the binder material, but its performance isn’t great. After just 500 charge-discharge cycles, typically only 65% capacity can be achieved in a battery using PVDF. We’ve all experienced this when our smartphone battery no longer lasts a full day like it did when the phone was new, but such experiences could soon be a thing of the past.
The JAIST team discovered a new, and almost unpronounceable new binder material called bis-imino-acenaphthenequinone-paraphenylene (BP) copolymer. The good news is, BP allows a battery to maintain 95% capacity for more than 1,700 charge-discharge cycles. In other words, it allows a lithium-ion battery to be fully recharged daily for almost five years, and possibly even longer. That’s according to Professor Noriyoshi Matsumi who led the study.
According to Matsumi, “The realization of durable batteries will help in the development of more reliable products for long-term use. This will encourage consumers to purchase more expensive battery-based assets like electric vehicles, which will be used for many years.” It’s certainly great news for our smartphones, tablets, and laptops, but even better news for electric vehicles where the lifespan of the batteries they rely on is so important, as is the range they offer.
