I think you are about to hit a "manufacturers warranty" issue here. If you add extra battery cycles, you are basically doing a lot more miles. Clearly this is serious for the vehicle warranty and I would expect you pay a lot for that. BTW I have a number of high capacity Li batteries, and get nowhere near 3000 cycles from them, despite there being a lot of "load management" electronics inside. At about 1500 cycles they are probably at half capacity, why you think vehicle batteries will be better is beyond me, as they get far more high rate charge / discharge cycles. Second hand electric vehicles often have trouble with batteries, probably why they are sold, and warranties on batteries are probably unobtainable. Battery storage is very unlikely to ever provide cheap power, it certainly doesn't today.

I don't think the average bear is going to understand what is best for them. There are going to be some very angry car owners when the grid has knackered their car battery and the car dealer says, "Nothing to do with us guv".

David Stone said:

I think you are about to hit a "manufacturers warranty" issue here. If you add extra battery cycles, you are basically doing a lot more miles. Clearly this is serious for the vehicle warranty and I would expect you pay a lot for that.

There are only a select few models (I thin you can count them on one hand) out there in the UK that are capable of V2G.

You might be right in terms of the warranties, but I'm not conversant with the battery warranty small-print for those models - I guess it would be easy to check. I understand the most prolific model is the Nissan Leaf.

David Stone said:

BTW I have a number of high capacity Li batteries, and get nowhere near 3000 cycles from them, despite there being a lot of "load management" electronics inside.

This definitely depends on the battery chemistry and physical battery architecture ... and what profiles the batteries were designed for in the first place. What's good for one particular battery is not always true for all.

David Stone said:

I think you are about to hit a "manufacturers warranty" issue here. If you add extra battery cycles, you are basically doing a lot more miles. Clearly this is serious for the vehicle warranty and I would expect you pay a lot for that.

There are only a select few models (I thin you can count them on one hand) out there in the UK that are capable of V2G.

You might be right in terms of the warranties, but I'm not conversant with the battery warranty small-print for those models - I guess it would be easy to check. I understand the most prolific model is the Nissan Leaf.

David Stone said:

BTW I have a number of high capacity Li batteries, and get nowhere near 3000 cycles from them, despite there being a lot of "load management" electronics inside.

This definitely depends on the battery chemistry and physical battery architecture ... and what profiles the batteries were designed for in the first place. What's good for one particular battery is not always true for all.