Quantum Turbo SC Battery Pack, mint cosmetic condition but I think needs battery

About 6 years old but only used a handful of times, one female owner, original price $550 it's been sitting in my camera bag most of the time so maybe not being used frequently did something to it, because looks like it doesn't hold charge for very long. so must likely needs a battery replacement, hence my asking price. Comes with a power cord and connecting cable. Ships from Washington State via USPS priority mail within 1-2 days. thanks