6-Pack Rechargeable 9V Batteries, High Capacity 1300mAh 9 Volt Lithium-ion Long Lasting Power, USB-C Recharge with 2 in 1 Charging Cable for Smoke Alarms,Multimeters,Toys,Microphones,Walkie-Talkie

these do have a charge when you get them so you could use them right out of the box.however, it is not a full charge, so you will need to charge them before expecting them to last any time at all.there is really nothing in the way of a manual or instructions that comes with them, but it is quite simple to use and charge them.

They charged quickly and work well. I have them in a few devices including remote control cars. They work well definitely get them!

I used these to power some led Christmas trees over the holidays along with some other lithium ion batteries I have been using for a few years. These batteries charge to a little over 9 volts each whereas my other batteries charge to about 8.35 volts so I am pleased that the trees are a little brighter with the new batteries. The new batteries last about 4 days going continuously before the lights go out, but the older batteries are still going for a few more days. The older batteries are listed as 450mah, so I doubt these batteries are really 1300mah (but that may be dependent on how it is measured since I am judging it to be time for a recharge when the flashing lights go out and there might still be lots of actual life left for some applications). It only takes me about 1.5 hrs to charge them so I’m happy with the purchase and would recommend them. I only took off one star because of doubts about the real world capacity of the batteries. I have gone through 3 or 4 charge discharge cycles and haven’t seen much change in life in my application but your mileage may vary. Overall seems to be a good product.

Here is how you can test battery capacity.Get approximately 360 ohm resistor for junk or 25 cents new.Actual resistance can be lower for quicker test.9v / 360 ohm = 25 ma in my case.1300 mAh battery should last 1300mAh/25ma = 52 hours.With my $2 HF Multimeter, I am verifying current, 24.6 mA, close enough.The meter actually has a built in resistor for battery load testing - use that, and you don't even need a resistor. To make it fun, the meter in the pic is also running off one of these 9v batteries.Let's say I get 30 hours life from this setup. The current after 30 hours drops to 22.2v and the voltage drops to 8.0v. This would be an average of 23.4 ma for 30 hours = 702 mAh compared to rated 1300. This is just an example, my test is still running.My goal as an electrical engineer is to teach you a very simple method to test your own batteries with inexpensive equipment. I actually have a battery capacity tester, but it is too expensive for the casual consumer. The above method gives the same results as the expensive device, but is not automatic, and does not read out in mAh - you have to do the math.I have tested many chargeable batteries of all types. I am rooting for these 9v, as there are few options in the rechargeable 9v world. These are the first I am testing with an inboard charger, which is both clever and silly to include a disposable charger for every battery. Including the cable is also impressive.Documentation is poor on the technology. Actually, there is no documentation in the packaging. The LED is red when charging, and green when charged, and that seems to work fine. I will learn the time required to charge from dead to full, and thus the charging current.

Why did you pick this product vs others?:I don't write reviews often. This product sucks. These batteries do not last despite being rechargeable. Just get the non rechargeable ones. Placed it in my smoke detector. Had to replace them 2x already despite them being fully charged each time. Non rechargeable ones last almost a year without issues.

I got these for my TENS unit and I feel soooo much better using it knowing I’m not just using up and throwing away so many batteries. I think the world should switch to rechargeable. I love that I can recharge these with a micro usb cable, incredibly convenient

I bought theses because my driveway motion detector goes through a normal Energizer battery in about 10 days. I had hoped these would at least last that long but that was not to be. After six days, it was totally dead. They might be good for low usage applications and they fit normal 9V battery compartments perfectly, which I cannot say for Lithium 9V batteries which would not fit in the allotted space in my motion detector, but they do not hold a charge long enough. Even though both batteries were charged up completely in the beginning, the one in use was dead in 6 days, and the other, just sitting there, was on its last leg also, taking as long to charge back up to full charge again as the one that had been drained in the motion detector. Maybe in uses in items like a small radio or backup for an alarm clock they would work better, but for my use, they are a total bust.The seller contacted me offering a full refund. I countered saying a half refund is more fair and I hope he takes me up on it. I changed my rating from 1 star to 3 stars. 1 star for product, 5 stars for customer service. So I figure. 3 star overall. While I would not buy this product again, I would most certainly buy from this seller again.

It keeps my electric shock therapeutic device going all day on a single charge continuously. I'll update and remove a star 🌟 if it becomes a "duck".