EEMB Lithium Polymer Battery 3.7V 3700mAh 103395 Lipo Rechargeable Battery Pack with Wire JST Connector for Speaker and Wireless Device- Confirm Device & Connector Polarity Before Purchase

I got this for an airsoft pistol and learned that said pistol needed higher voltage to run properly. Said pistol uses a faux extended magazine to house the battery, and this one was a reasonable fit. I'm a bit disappointed it didn't work out, but I have plans for this battery. I own and operate some 3D printers as a hobby and this battery will work great for a few LED lamp projects I have in mind, but I digress. I appreciate the fact that this battery has a built in low voltage cutoff, though I have no intention of testing it. I see a lot of folks use this for microcontroller applications though I can't comment on this battery's efficacy there. For test running LEDs with a buck converter, this battery is working great, it has a much higher capacity compared to the numerous tiny single cell Lithium batteries I have laying around, yet it's compact enough to fit in portable lights. As for the battery connector, I again can't comment. I removed the molex connector that came with this battery and soldered a Deans connector onto it's leads (after testing it on my programmable charger with the molex connector on) and I haven't had any issues. I'm very pleased with this battery, and should I ever need one like this for a future project, I'll gladly order another one.

It’s a very long lasting battery. Got it for a project to use with Leds and stuff; it works great and lasts long

Check polarity first! The wires on the battery came backwards but its an easy fix, the battery is pretty powerful and has a good battery life

Got this to supply power to my arduino LTE shield. Not sure how long the battery lasts, but it works. 1 caveat is that I had to reverse the wiring polarity as my project plug had + / - reversed from how the battery came. Simple depin and repin and was up and running. Would be nice to calculate my estimated runtime with my project, but not sure how to figure that out yet. Hopefully it's at least a handful of days.

Nice compact battery with connector. I changed the connector polarity by carefully removing the sockets and changing sides. I used a mini screwdriver and microscope to “unlatch” the sockets. If you are familiar with this type of connector this is fairly straightforward. If not you might want to look at the sockets on JST site to see the latch tab that holds them in. Perhaps the batteries could be shipped with the connector loose to have the polarity determined by the user. I use them for the U-Blox C099–F9P gnss rtk unit and they are great and last a long time. (Haven’t run one out yet even with half day of work)

Bought second as first still going strong under all loads of FPV camera (e.g. 200 mw) on a homemade transportable platform of multiple RC aircraft. Holds voltage and capacity in cold and hot Texas winter and summer temps. I use small battery charger on these and takes awhile to charge fully when drained which almost never happens. If you need longer run time with device that can manage the added weight, this is the best deal I've found.

Excelente batería

I wish I had read the reviews closer before plugging this dude into my Adafruit Lithium Ion Solar Charger. I think it may have blown it out. I rewired, and will see how the battery life is; once I get a new charger...

Ik ben tevreden met de snelle levering van de accu's, alleen bij mij zijn niet helemaal oke. De accu's willen niet fatsoenlijk laden, en zijn naar mijn idee zeer snel leeg.

La compré para sustituir otra batería dañada de una linterna…Funciona correctamente

Ich hatte diesen Akku vor kurzem in ein LED-Taschenlampe eingebaut. Fazit: Prima Akku der für seine Größe eine erstaunlich hohe Kapazität hat und somit Verbraucher in meinem Fall eine LED-Taschenlampe lange Zeit zum leuchten bringt.

I am currently amusing myself making portable audio equipment. The main concern with Lithium battery power is safety. This battery has battery protection built in. I can use it with cheap chargers and with cheap and poorly specified Bluetooth modules and class D amps with confidence that abuse cannot be catastrophic. It also has a handsom capacity. My diy Bluetooth amp lasts ages using it 3.7Ahrs! I must add a further caution for users after having read other comments. Li batteries are dangerous when charged incorrectly particularly when overcharged. This one has a protection circuit built-in. However, I would say that it should not be charged directly from the likes of phone or other plugin usb power supplies. Use one of the many cheap charger boards available that will automatically reduce the charge current near full charge and shut off charging when the voltage reaches 4.2v. the battery will also last longer and be safer if the charge current is limited to 1/3rd of capacity or less. No more that about 1A to 1.2A. This increases charge time but is safer and less fatiguing on batter life. Some usb supplies only limit at 2A or even 3A and have no shut down. Be cautious!

Perfette