EV Batteries do degrade due to many differing reasons, in this we consider two common aspects happen in Sri Lankan conditions and how a battery exercise may help. Please note that the content is still under discussion among specialists, so you may need personal/professional supervision.
There are many wrong usage practices of the EV s in Sri Lanka causing batteries degradation and even wrong calibrations. We have spoken of battery preserving tips
Here is a link: https://evrev.lk/2019/05/12/ev-%e0%b6%b6%e0%b7%90%e0%b6%a7%e0%b6%bb%e0%b7%92%e0%b6%ba%e0%b7%99%e0%b6%b1%e0%b7%8a-%e0%b6%af%e0%b7%92%e0%b6%9c%e0%b7%94%e0%b6%9a%e0%b6%bd%e0%b6%9a%e0%b7%8a-%e0%b7%80%e0%b7%90%e0%b6%a9%e0%b6%9c/
But the ones which has not being used well and/charged will undergo degradation.
Follow this too: https://evrev.lk/2019/10/03/mandatory-battery-tip/
One major reason behind the capacity loss is the loss of electron movement. This is called lithium plating. Simply the electrons get collected on to the anode preventing its travel which causes capacity loss. (not the only)
The longer a battery stays at high SoC, the more lithium plating occurs, and the more capacity is lost.
What can you do to recover?
Leave the SOH between 30% to 40% for a month or two. Let the ions get detached and back in action.
Tough? you may run if it’s a must, but give only the bare minimum charge.
The recovery effect is not fully understood and needs further research. And we do not take any responsibility for success or failure.
Atop the degradation, the smart batteries (digital) may release erroneous data, where your BMS will interpret and CAN will display differently.
To correct this error, we advise a recalibration.
Discharge the battery from 100% to 10% on a gradual and an even pace. Then go for a L2 charge.
Also try discharge the battery from 100% to 10% on a gradual and an even pace. Then go for a L3 charge.
We may try this for multiple times, under the observation and monitoring with the instrument cluster data on efficiency, temp and also the leaf spy data on internal resistance, temperature, SOH and more.
You got to understand that these procedures may result differently based on your type of EV, usage, cause/s of error, battery status. So please proceed with your own discretion.
The conditions are different in Sri Lanka although we referred several technical papers done overseas.