2 Pack Rechargeable 9V Batteries, 1300mAh High Capacity Lithium-ion Long Lasting 9 Volt Batteries with 2 in 1 USB C Fast Charging Cable for Smoke Detector,Alarms,Microphone,Metal Detector Multimeters

It is a novel way of charging these batteries using a USB port. I am super happy with the function of these batteries and I am using a number of these in smoke detectors. To tell you the truth I am still amazed at the USB charging function for these 9 V batteries. These batteries have performed flawlessly for me. I only wish that I had known about these batteries sooner.

Excelente producto . Funciona como lo publicado .

Batteries made it through 10 to 15 charges. After charging further than that, battery started to lose power and remain dead upon use.**Update. Changed to 4* because of customer service.

These have proven to be very good quality 9v batteries, they arrived in perfect condition and after a quick charge they were ready to go.Charging these batteries is simple with the type c connector, all it needs is a phone charger. Keep in mind that a laptop charger will not charge these due to the higher wattage and safety tech.I've ran a pretty beefy DC motor on a single charge for 9 hours and 45 minutes straight without any problems, so these get 5 star in my book! Currently I do not have any electrical measurement device, so I cannot provide you with accurate amperage or voltage ratings, but in my testings the speed of the DC motor reached high rpms similar to that of a tradition 9v battery.

These are great! Sure beats paying thru the nose gor just one!! The charge lasts pretty long. Am using these 9v. on my garage door opener and a Tens machine.

I do a lot of battery testing for use in various products. I have tested pretty much all available brands of lithium-polymer USB rechargeable batteries currently available on amazon. I bought a pack of 8 of these about 2 months ago and tested them.Results:2 of 8 failed to work right out of the box6 of 8 did take a charge the first timeWhen used in a device, all 6 lasted much less time that older 9V Li-Po batteries that were rated only at 650 mAh. I conclude that the real capacity of these batteries is more like 350-450 mAh, not 1300 mAh as advertised.Upon recharging, additional batteries began to fail.After only 4 recharge cycles, all but 2 of the original 8 batteries have failed and will not take a charge, and will not deliver usable power.I would not buy these batteries again.

I use this in our door alarm sensors. Now they last a lot longer and reduce time spending charging batteries. Even came with a twin charge cable. Nice touch.

These are amazing batteries. Gr8 product and fast delivery. Thx AMAZON