KBT 12V 1200mAh Rechargeable Li-ion Battery, 12 Volt DC5521 Male Connector, Replacement Battery Pack with Charger Compatible for 12V Devices RC Car, Boat, Robot, DIY, LED Light Strip, CCTV Camera

Using this battery pack, I built an oddball one-off device used in broadcast production that's too complex to explain here, but suffice to say this little battery pack works great in it and lasts a good long time. The included charger is a nice touch, and it indicates with an LED when the pack is fully charged. The cable termination options are great for DIY applications of all kinds. My only issue is that the charging input, a female DC coaxial jack, also has 12V on it. This is not a big deal but the pin could easily be shorted to the shield if something metal got jammed in there by mistake. I don't want to try it and find out what happens, but hopefully there is some protection in the pack to prevent a meltdown. Seems like a diode wired into the pack could prevent this.

Great project power sourceUsed with a Bluetooth amplifier set up, 30 watt speakersNo problem running 4 the day

I bought this to power a strobe light on the back of my kayaks. Works great.

Lots of power. Good value.

The battery charging could be better. It works!!

Great for lightweight portable QRP radio operations in the field. Small size and cabled right for my application. Very handy.

Great rechargeable battery. Good connecting functionality, holds a charge, recharges well.I have been using this with a buck step down converter to power 5v arduino products. With the wire coupler, connections are easy!

Works great with the lights on my helmet