Hi,
yesterday I noticed a very interesting article on Slashdot.
In short, according to the article, we may have been charging Li-Ion accumulators in a very sub-optimal way for the past few decades. In their tests, they found that the standard constant-current charging method leaves the cell almost completely dead after 1000 cycles, retaining just around 38 % capacity. By changing the charging method to 2 kHz pulses at 50% duty cycle and double the peak current (so that it averages to 1C), the cell aged much better, retaining almost 82 % of capacity after 1000 cycles.
If this really works, it is a pretty significant advancement. You could easily double the useful life of the battery, and it does not rely on some new vaporware chemistry that may become available in 20 years – you could do it today. At least with cells that use the chemistry they tested; I’m not sure if it’s supposed to work equally well with all Li-Ion types.
It may take some effort to turn the paper into practical charging equipment, of course. Standard Li-Ion charge controllers probably won’t be too happy if you try to feed them a square wave, so it will either require new ICs to be designed, or rolling your own charging solution made from discrete components.
Apart from that, I imagine there may be other problems to solve, like EMI (since you are rapidly switching pretty high currents) or even audible noise, if the 2 kHz wave causes vibrations (coil whine etc.) But if there is any company that has good incentives to look into it (rather than protect their side business of selling replacement batteries), it’s probably Framework. So I’m curious to hear your thoughts on this. 