Car battery damage?

[Fordulike]

Stupidly I left the main lights on the car, and it ran the battery down to 7.5 volts. This wasn't enough voltage to start it, but after a boost, it started fine.

Ran the engine for a good while to top the battery back up.

My question is, would draining the battery down to 7.5 volts have caused permanent damage to the cells?
Everything appears normal, as it was before the mishap, but I'd rather fork out for a new battery if I'm likely to have screwed this one up.

 

[Alan Quay]

I've done worse to them and they have survived for many years after the event.

I'd get a set of jump leads (£10, eBay), chuck them in the boot and risk it.

Perhaps check voltage after a few days. Should be around 12.7v.

 

[Fordulike]

I've done worse to them and they have survived for many years after the event.

I'd get a set of jump leads (£10, eBay), chuck them in the boot and risk it.

Perhaps check voltage after a few days. Should be around 12.7v.

Thanks for the heads up Alan. Will be getting a new car in September, so trying to keep this one alive on a budget