These so far have lasted longer than your standard battery pretty charge and charge very fast. Each set comes with a charger cable that charges 4 batteries each.Potential savings if batteries hold up as long as claimed is in the thousands per set of batteries.They currently only have 4 packs which is really only enough for 1 maybe 2 devices. Larger packs with incremental price breaks would be great.I did get 1 battery that the head was soldered slightly offset so it doesn't fit into really…

Great replacement for smoke detectors, haven't had to put on second change yet, quick charging time, and the charge indication is a benefit.

Slightly lower voltage than a standard disposable 9v battery, so they wouldn't be good for smoke detectors or anything with low voltage detectors. I use them in continuity testers and other network construction tools and they work perfectly. No more throwing away a battery of I forget to turn something off, just recharge them and pop em back in. I certainly don't miss going out of my way looking for battery disposal bins.

…for some reason when I plug these buggers into my active pickups on my noodle hammer, aka bass guitar, it makes a high pitched squeely feedback noise that normally doesn’t happen. Maybe I need a different kind of battery? I don’t know. But they charge well and seem like they’d work for anything else. They feel a lot lighter than regular 9-volt jobs.

These are claimed at 5400mW/hr capacity which translates to about 700mA/hr so should be fine for most low power applications requiring limited attention over long periods. Mine actually have a fully charged terminal voltage of 9.16v which is very good for Lithium Iron. They also come with a nifty built in mini USB port for use with ubiquitous standard USB wall chargers.There is however a problem. The internal switching voltage inverter which creates the >9v output and allows this simple…

The is are jus what I need. I go through about 5 or 6 9v a week for my TENS unit on my back. That is about $22 or more a week. With the is I save money and always have a fresh battery.

Full charged one via USB and discharged with an IMAX B6AC v2 professional charger / discharger down to 6.4v (3.2v per cell as this is li-po 2s). As seen in the picture measured capacity is 493mAh. With a nominal voltage of 7.4v this amounts to only 7.4×493 = 3648.2 mWh and not the claimed 5400 mWh. The manufacturer needs to specify discharge rate used for measuring capacity. Due to this I canceled the second order of these batteries that I placed.Adding an extra star for the customer service…

Once a year I have had to remember to buy new 9-volters for the fire alarms as those were the only devices I still used them for. When I recently bought a couple of new items online without knowing they would require 9-volt rectangle power centers, I looked to Ebay to order a few. To my delight, I discovered these new, or new to me, batteries which could be recharged utilizing a USB connection. Never again will I be dangerously low on power for the critical smoke alarms but I will have adequate

Couldn’t use the product because batteries wouldn’t keep a charge. I’m very disappointed to say the least. Thanks for attention!

I was hopeful that I could use these batteries to extend the time between battery replacement for my First-Alert smoke/carbo monoxide alarms. I had good experience with EBL before and it was a brand that I trust. My first set of batteries lasted only barely 2 months before my smoke alarms started beeping. I now learned that these are not good for First Alert smoke/carbon monoxide alarms. Unfortunately, my first set of 4 was ordered two months ago and I could not return them any more.[7/2/2022…

I have an acoustic guitar with an electronic pickup that is powered by a 9 volt battery, and frequently replacing these batteries became expensive. The EBL batteries with USB charging cord are the perfect solution. All four batteries can charge at the same time, if desired, using a single USB input. I install one in my guitar, and keep the other problems 3 in my guitar case accessory compartment as spares, so always have a fresh battery ready for use. When I get down to using my last spare…

Excellent 9v USB rechargeable lithium batteries. Bought 2 4-pacls.Note: These are 540 mah batteries. Most rechargeable 9v lithium's are 600 mah (battery charger required). 60 mah less is an acceptable trade off for being USB rechargeable Probably needed the space for the circuitry.Will update review early 2023 with more info.

It’s hard to review batteries but they exhibit all the behaviors of good rechargeable Lithiums. I don’t know about their life yet.

Won't go through all the details. Let's just say that, through a lifetime of injuries of many types, pain is a constant companion. Neurosurgeons cringe at my MRI's. Even the spinal implant didn't help, but tens units DO. Thing is, they eat batteries. Eat them, and eat them, and eat them. I can use 2 9v's in a day. Don't ask me why I waited so long, but I'm *really* glad I found these. They hold a charge well under a heavy load, deliver what I need for hours, recharge quickly. If I'm out and…

These rechargeable 9 volts are absolutely great. They work very well, super easy and convenient recharging. The problem I have is I bought these batteries to use for my active pickups in my guitar as well as my guitar pedals. These batteries admit RF noise making them pretty much useless for those applications unless you are looking for that classic hum tone. I've read others have used RF chokes to control the problem, but I really don't have the room inside my pedals to do that and I'd rather…