On the calendar degradation

Hello Paul,

I'd like to calculate the calendar degradation occurring in a battery that is not cycling at all. From SAM I'm getting values of calendar degradation greater than 100%.
In the following graph you can see the "battery relative capacity to nameplate (calendar) (%)" and the "battery relative to nameplate (%)" I'm getting:
 
 

Both "battery relative capacity to nameplate" don't look right because at the end of the lifetime I would expect some calendar degradation.

Please can you review why that is happening?

Many thanks in advance

Best regards
Fran

Hi Francesco,

SAM's model for Lithium-ion NMC/Graphite assumes that the battery experiences some initial capacity fade at the beginning of its life. The initial capacity is slightly over 100% so that it levels out to 100% within the first few months of use.

Best regards,
Paul.
 

Hi Paul,

many thank for your reply.
The system I was modelling is a li.ion LFP not NMC. 
My question then is: how should I model a battery that at day 0 has 100% capacity and starts degrading according to li-ion lfp calendar degradation?
Many thanks
Best
Fran

Hi Fran,

You can use the "Custom" calendar degradation option to define your own degradation curve that starts at 100%.

Best regards,
Paul.