Battery degradation?

[OriginalBigAl]

I,ve seen its normal to get battery degradation at a rate of around 2-3% a year.
Is the time ( a year ) the major factor in this rate, or the number of recharge cycles or just general usage.
For myself (MG4) NCM battery ,I estimate an annual usage of around 7500 km or 30ish recharges at 40kw with the occasional 100% charge so less than average usage. I intend to keep the car for a long time so I would be interested to know how these rates are calculated, cheers.

 

[Lovemyev]

I think there is a few factors that can contribute towards this really.
Number of cycles for sure, also how is the pack charged ?.
What is the percentage split when taking on a charge, is it mainly from a A/C supply or mainly from a D/C supply ?.
Is the pack regularly run down to a low SOC before charging, then is it then charged back up to 100% SOC then left sitting for days on end with a fully charged pack.
Is the car subjected to numerous hard pull acceleration etc.
Some of the above items are not regarded as good practices for long term heath of your HV pack, if you intend to keep the car for a while.

 

[Deleted member 6627]

Be aware that caring for your battery could be the more expensive option. If you can get a battery change under warranty then your car is likely to last longer. Not sure how easy this is with MG or whether they will just argue the case. And even if they give in I suspect a replacement battery will take them forever to supply.

Just don't assume that caring for your battery is the best option for longevity of the car.

 

[Hotlush]

I,ve seen its normal to get battery degradation at a rate of around 2-3% a year.

I think, generally, the first year sees that and that will be the biggest drop, after that you're talking more like 0.5%.

You also have to factor in that the battery itself has more capacity than specified. It can cope with a few cells dropping in performance as it will just "shuffle" around a bit and start using more efficient cells.

 

[TheArcher]

My 2016 Soul EV (27kWh battery, so short range) shows 94.2% state of health. We've been charging it on the granny cable since we got it 2 years ago and last 6 months up to 100% overnight. (Can't wait to get my ZS LR!)