Rechargeable 9V Lithium USB Battery 860mAh with 4 in 1 Charge Cable, 9 Volt Batteries 6f22 for Smoke Detector Alarms (4 Pack)

Good value andWorks well. Easy to charge. So far battery life good

These are great, easy to plug and charge. Hold a long charge. Green light indicates full charge.

Great buy! We bought these for an outside dog bark deterrent. OTC batteries last about one week. At about $4 per battery... We charged these suckers up, placed in deterrent and the battery lasted about 1 month! We are super impressed. We knew we had to share!

Didn’t work

I was concerned that the voltage might be a little low as I experienced with other rechargeable 9v batteries. These work well. I think the charging cables are pretty cool. They are lighter than the typical 9v.

That fact that these are rechargeable makes them great. I save so much money on not having to buy so many batteries.

I used these in my smoke alarms as I typically replaced the alkaline batteries annually and thought this would be a good choice environmentally. This was an epic failure. Unbeknownst to me, I installed these batteries and went on a week long vacation. Only recently did I test the smoke alarms and all 8 of them were not working. I recharged the batteries and reinstalled them to only have the smoke detectors chirp indicating a low batter after 24-48 hours . I removed the rechargeable batteries and switched back to alkaline two weeks and no issues. These batteries are not worth the investment.

Great batteries / price compared to buying reg 9 volt ones.