You can replace the batteries.
My first battery box ... too small to jump stuff... was 2 years old when I bought it new, at Wally World off a clearance rack.
it lasted 3 years, I replaced the batteries and it then lasted 3 more years ..... it met it's demise when I crossed something and melted it down.
My first Jumpstart came from one of the Cunningham traveling tool shows. I used it so much for jumps, portable power and other stuff that it stayed on the charger constantly, and it lasted 5 years. The 2nd came from Harbor Freight and lasted 3 years, with lots of use before it died.
Before I could replace the batteries in this one, the wife bought me a new one form Wally World for our anniversary.
Matt