The cover in comprehensive policies depends on the cause of the fire. It does not cover the damage if the fire is caused by the breakdown of any EV part.
While the fires are being blamed on hot weather to other things, experts say thermal runway which leads to heating up of the battery may be the reason. In that case, the claim will be rejected as also when modifications are made to the vehicle which may have contributed to the fire.
Also, there have been instances of detachable batteries of EVs exploding while being charged and so won’t be covered as well.