Car Battery like new 7x10

Car Battery I bought brand new under 6 months ago thinking electrical problems we were having was the Battery. The battery was not the problem, the car died and we bought a new car that actually has 2 batteries. Other battery has been tested and is good as gold. Has a 3 warranty that sadly cannot be transferred but it's almost new and don't want a good battery to go to waste. Bought it for close to $140.