I'm not so sure on v power shelf life if left in a container?

I've had a 25ltr container sat in my garage for over a year (unopened) and recently used it.
However I left 1ltr in another container and forgot about it. It was full of moisture.

Your be surprised how much moisture it creates when opened then left , so wouldn't suggest leaving it in your cars tank for weeks then use the car like normal etc.

Steve