Review on Snapper XD Cordless Electric Tools Battery: Briggs & Stratton 82V MAX 2.0 Lithium-Ion by Randy Butler

The 2.0A battery is a smarter buy; you spread the risk of battery failure across 2 batteries and pay less money for the total capacity (2.0A is $125 from some sellers). If one fails, at least you still have another battery. Also, running a high capacity 4.0 battery on a tough lawn gives it a lot more time to overheat; heat is the enemy of Lithium Ion battery life. Get the 2.0 capacity. In addition 1) let the batteries fully cool down before charging and 2) Do NOT let the battery sit uncharged for longer than a couple hours. 3) Do NOT try to continue using the battery once the device gives you the first low battery warning/shutoff. You'll get a lot more mileage following those tips. I've run 3 of these batteries hard for 3 years on wet, thick grass. Recently lost one because I didn't follow the rules above.