
All of our portable electronics—phones, laptops, tablets—watches—all rely on rechargeable batteries to run. These batteries usually have two limiting factors—how much charge they can hold (how long you can run on a single charge). And, also, how many times you can charge them before they start to fail. And with more devices (for example, most contemporary Apple products) having batteries you can’t replace, this durability becomes more important. As well as the importance of being able to more efficiently make these more durable batteries
But in a new “Nano Express” article in Nanoscale Research Letters, researchers from the School College of Chemistry and Chemical Engineering at Shanghai University of Engineering Science and the Department of Chemistry of the University of Science and Technology report on a possible answer to this problem. What Linin Wang, Kaibin Tang, Min Zhang, and Jingli Xu have found was a an easy, efficient, and cost-effective way to fabricate a new kind of anode (one end of a battery system—the cathode being the other) using magnesium-doped zinc oxide porous nanosheets that can maintain their electrical capacity even after more than 300 charging cycles.
The problem
Zinc oxide has many advantages as an anode material for lithium-ion batteries, including abundance, low cost; it’s non-toxic, easily produced, and chemically stable. The main drawback, though, is that these anodes lose volume over time as the charging cycle leads to the formation of alloys from the battery’s lithium atoms with the zinc. And as this happens, and the anode loses volume, the battery loses the ability to charge.
While there have been many possible approaches to this problem investigated, and while magnesium-doped zinc oxide has been investigated for many other properties, and is relatively easy to synthesize, the authors point out that it has rarely been used as anode materials in lithium-ion batteries.
Results
What Tang et al. found was that the cavities in these porous nanosheets seemed to effectively suppress the volume change effects of the lithium-zinc chemical interactions during the charging cycles, leading to much more electrical durability over the course of the 300+ charging cycles they tested.
And the upshot? Perhaps the battery in your next iPhone might last for a lot more charging cycles.