40-Volt 4-Amps 4.0ah Rechargeable Lithium Ion (Li-Ion) Cordless Power Equipment Battery for Kobalt

Bought as an extra battery for older Kobalt mower since the original one that came with mower is aging out and runs out of power too soon. The newer version fits, works well in the mower, can be recharged in my original charger, and holds the charge long enough to finish cutting the front lawn as did the original one when new. So far, very pleased with my purchase.

The battery is what one would expect today. They are too expensive, heavy, and only last about 25 minutes. Then it takes 2-1/2 hours to recharge it. If you have a decent sized yard with trees, you'll need two of them and maybe two chargers. Alternatively, you wait to finish the job. Kobalt is average when compared to others. It seems that my description above is true for all of them.

It works!

This new battery is working great; probably 30-40 minutes on one charge, not using the self-propelled feature. The battery we got with the mower started limping in the 3rd year. We can still use it in this its 4th year, but it only charges 4 lights worth and gives about 10-15 minutes on a charge. However you measure it, the battery is well worth the price, to avoid using gasoline.

A lot less than lowes. Runs longer

The 4ah lasts longer than the 2.5ah. Batteries arent cheap. It has held up well to the red oak and white oak firewood used on 5" to 12" stem logs left after electric cleared our property. I have 2- 4ah, 1-2.5ah and 2 chargers. The main drawback is the overtemp protection. The saw and chargers will not operate when hot (really warm). So I split and stack or load truck during this downtime. I love the fact no Loud noise, starts every time, no fumes, no gas mix.

This was a secondary back up for a mower I already have. Helps me finish mowing the yard in one day. Very helpful to have. Recommend.

It stopped working after one winter. I bought the battery in September for a lawn mower, and it was working fine, but I barely used it. Come late March, I try to charge it, and get no light from the charger. Other batteries charge fine. There is no warranty service from Amazon or from the seller. Kobalt told me their warranty extends only to the original purchaser. So, I saved a few bucks compared to what it would have cost me at Lowe's, but now I need to buy a new battery only 7 months after the initial purchase, most of which were winter, so the battery was not even in use.