Rechargeable 9v Batteries USB 9 Volt Battery for Smoke Alarms 3700 mWh 9v Lithium Battery with 2-in-1 USB-C Charging Cable and LED Charge Indicator, 2-Pack

I opted to use these batteries based on the position of the charging port in line with the wire tunnels in my Stratocaster clone. With a ribbon cable and a mounted port on the center cover, all I need to do is plug in the guitar when the pickups get weak. No need to open stuff up.I’m planning on doing the same on a Cort multiscale in the next several months with the spare cell. The main benefit is that it is so easy to forget to charge, and I can literally plug in the guitar on the go to my Anker iPhone charger battery I have in my kit. You can play as it charges without issue.Pickups I’m using are Wilkinson active humbuckers I upgraded the guitar with. Gets heavy metal overdrive without needing to spend big money!

I have nine reasons why this may give you a vault of shock about these batteries. One it comes with 2/9V batteries number two has a slot that you put the charger in to batteries plus L.E.D. Indicator to let you know the Battery life three it has a USB charging cable with two charging adapters on it to charge the batteries at the same time. Then you multiply that by three other things one convenience two ease of use and three available when needed, and that gives you nine reasons why this will be a shock to your charging system to have these batteries ready to go!!!!

Works as advertised

These rechargeables are amazing. I have more and more been moving to use mostly rechargeable batteries for most of my needs, and I can't overstate how much I like these specific batteries.I previously didn't have any rechargeable 9 volts, so I was happy to add them to the collection. I honestly had low expectations and have been extremely impressed with these so far, even though I have only used one is a smoke detector at this point. My favorite thing about these is that they charge via cord, rather than needing a dedicated charger. The dedicated charger isn't such a big deal for my AA and AAA batteries, as I can use the same thing for each of those sizes and the charger is quite small and portable, and I go through those sizes frequently enough to make it worthwhile. I imagine if I needed to have a charger just for charging 9 volt batteries, it would probably go missing since I use this size so infrequently and the need for recharging would not be consistent. Anyway, as I've been rambling about, these can charge via the same wire you use to charge every other usb-C device you own, and they also included a dual-head usb-C cord so you can charge both of these at the same time on one plug. Awesome.I also like that these came in a little plastic carry case. It isn't anything super fancy, it's just a very nice touch and gives me a proper place to store these when needed.These are great rechargeable batteries at what I consider an excellent price for the pair. Ease of use and ease of charging makes these the perfect choice for a rechargeable 9 volt.

Working as intended & lasting great so far! We'll see how well this will hold up. I'll follow up with updates if there are any changes.Overall I would highly recommend purchasing these Rechargeable 9v Batteries USB 9 Volt Battery for Smoke Alarms 3700 mWh 9v Lithium Battery with 2-in-1 USB-C Charging Cable and LED Charge Indicator, 2-PackFinally this review is of my own honest opinion & is not swayed in anyway by other influences.

These batteries run down faster than non rechargeable 9 v. Batteries. Don't seem as strong when fully charged. That being said. They get the job done and run my TENS unit pretty well. There are enough batteries that you can always have a fully charged battery waiting.

These are not the first rechargeable batteries I've tried but so far they are the best. I play guitar and go through a lot of 9 volt batteries in my acoustic/electric and active guitars. I usually use alkalines as the rechargeable batteries I've tried in the past tended to die after a few hours and I wouldn't trust them to last the night when playing a show. But batteries have gotten a lot more expensive lately. It had been a few years and I know technology has come a long way since the last time I tried rechargeable so I thought I would give these a shot. I thought I would just use them for rehearsals but I'm really impressed with how long these last. I have gone all day many times with these installed and they lasted as long if not longer than alkaline batteries. I like the indicator light that lets me know when they are charged so there is no mystery. The best part is the price point is similar to single use batteries.

Decided to give these a try for a lifepod safe since that's about the only thing we have that uses 9v batteries. We have two of the lifepods and replaced the regular 9v batteries that were in them for about the last 2yrs. The standard 9v batteries were pretty much dead however they had enough juice left to enter the code one more time to open the pods one more time. Ordered these in middle of March, charged them up and installed. Have only opened the pods twice since that time so barely any use with the electronic key pad and today 4/29 went to open one of the pods and it was completely dead so had to find the key for it to get in. Decided to check the 2nd pod and completely dead as well as the first. Batteries didn't last 2mo with barely any use so can't recommend these batteries. Maybe just a bad set but the standard 9v random brand name that was in there before lasted over 2yrs without issue and these crapped out in less than 2mo. Not sure why truthfully as most reviews look good but can't risk trusting these if it came down to needing what's inside the lifepods in an emergency.