Picking the battery was time consuming. I had to not only try and match the voltage of the original 24V pack but also keep the size constrained to fit inside the original battery case.

I picked a custom $125 LiFePO4 battery with 25.6V 4500 mAh from AA Portable Power Corp. (http://batteryspace.com) for the following reasons.

• Battery management system (BMS) was pre-installed.
• 18650 cells wired in 3 rows of 8 (8S3P) and did not exceed the inner dimensions of the battery pack.
• mAh and voltage are close to the original.
• Discharge current is 14 A. Well above anything the SLA battery could provide.
• Only 2 lbs.