My kids have had a power wheels for years. When the first 12v battery bit the dust I bought a new one for 80ish$. The new one bit the dust last year and the powerwheels has just been sitting in the back yard ever since. I was not going to buy a new battery since the wheels are out of alignment now and the kids rarely played with it. Well last week I was on YouTube and saw where people were converting them to 18 volt by putting Milwaukee batteries in them. I had a Ryobi flashlight that I never use so I dremmeled the head off and wired it up today. Kids are LOVING it again and have not stopped riding all morning. Easy swap out and instead of charging for hours for 30 minutes of play it's swapped to 30 minute charge for around 40 minutes of play. Wish I had thought of it sooner.