4 ms·

does anyone have knowledge of whether, once a battery starts losing capacity, does it do so in accelerating speed? My experiences with laptop and phone batterie

by fhe 5y ago

does anyone have knowledge of whether, once a battery starts losing capacity, does it do so in accelerating speed? My experiences with laptop and phone batteries suggest that they do. It took a couple of years for batteries to be reduced to 85% capacity, but from there it took only half a year for them to diminish to 60% or 50%.

theshrike79 5y ago
Yep: https://electrek.co/2020/06/06/tesla-battery-degradation-replacement/ https://electrek.co/2020/06/06/tesla-battery-degradation-rep... "Real-world data showed that Tesla battery degradation was less than 10% after over 160,000 miles (257,500 km)" According to the graph there's a slight dip during the first 50k and then it levels out to a steady decline. There is no data for batteries around 60% capacity, since there are none yet :)
- Buraksr 5y ago
  I have some done some tests on 2900mAh Samsung cells from 2008. I have tested about 50 cells so far that were pretty abused, meaning they were discharged to less than 2.2V for several months. This is very bad as their normal operating range is 4.2-3.2V if you are really pushing them. About half of the cells are effectively dead, internal shorts or electrolyte leaks. Included in this half are cells with mA discharge currents which is very out of spec. Not suitable for use. The other half lived with an average capacity of 2050mAh with a std deviation of 150mAh. This is only a degradation of about 30% which was pretty surprising to me.
  - fzzzy 5y ago
    If you leave a lithium ion battery pack at a low level of charge for a long time, it will kill it. If you don't, it won't.
Eric_WVGG 5y ago
My numbers almost exactly match yours. I’ve been using “Coconut Battery” for about fifteen years to track this on various MacBooks. The death spiral starts at 80%. Newer Macs and iPhones now get pretty aggressive about pushing users to seek service. Also worth noting that, as of Big Sur, MacBooks that are mostly used plugged-in will not too off past 80% until asked. I expect that this will pay off bigly for consumers.

by fhe 5y ago

theshrike79 5y ago

Yep: https://electrek.co/2020/06/06/tesla-battery-degradation-replacement/ https://electrek.co/2020/06/06/tesla-battery-degradation-rep... "Real-world data showed that Tesla battery degradation was less than 10% after over 160,000 miles (257,500 km)" According to the graph there's a slight dip during the first 50k and then it levels out to a steady decline. There is no data for batteries around 60% capacity, since there are none yet :)

Buraksr 5y ago
I have some done some tests on 2900mAh Samsung cells from 2008. I have tested about 50 cells so far that were pretty abused, meaning they were discharged to less than 2.2V for several months. This is very bad as their normal operating range is 4.2-3.2V if you are really pushing them. About half of the cells are effectively dead, internal shorts or electrolyte leaks. Included in this half are cells with mA discharge currents which is very out of spec. Not suitable for use. The other half lived with an average capacity of 2050mAh with a std deviation of 150mAh. This is only a degradation of about 30% which was pretty surprising to me.
- fzzzy 5y ago
  If you leave a lithium ion battery pack at a low level of charge for a long time, it will kill it. If you don't, it won't.

Eric_WVGG 5y ago

My numbers almost exactly match yours. I’ve been using “Coconut Battery” for about fifteen years to track this on various MacBooks. The death spiral starts at 80%. Newer Macs and iPhones now get pretty aggressive about pushing users to seek service. Also worth noting that, as of Big Sur, MacBooks that are mostly used plugged-in will not too off past 80% until asked. I expect that this will pay off bigly for consumers.