Battery range gone from 95% to 15% in 45 miles and now car stopped dead. Any ideas.

[dp124]

My Zs ev LR does a journey of 86 miles twice a week.
Today for the first time my partner used the air con departing with round 95% charge. She has just rung me saying the car now says 15% battery and a range of 24 miles. I suggested she went to a nearby Morrisons to charge. Car wont charge and has gone dead saying some unable to move message. Awaiting AA. Anybody got any ideas what would cause this battery degradation?

Message is unable to brake safely..

 

[Jomarkh]

That is quite a drop. What is the m/kWh showing?
Is your wife using a rapid DC charger or AC type 2 EVSE?

 

[dp124]

That is quite a drop. What is the m/kWh showing?
Is your wife using a rapid DC charger or AC type 2 EVSE?

Sorry dont know the dash M/KW display is showing. AA disconnected the battery and got it to a Tesco charger as there was some doubt about all the other chargers at Morrisons. Car charged on the MG supplied cable got back up to 13% and stopped charging. Now getting escorted to a nearby 50KW charger by the AA to try that.