4PCS 4S 4 Series Lithium Battery Level Indicator Capacity Module Ni-MH 16.8V 4 Sections Blue LED Display Electric Vehicle Battery Power Tester Li-po Li-ion

Good deal works well bright display

Works OK, but no instructions. I wanted to know more, so I measured the current draw and found it to be 35mA, which is very high for a battery checker. If you leave it turned on, it will drain the battery. So, you need to use a push button switch to momentarily check battery level. I think the LEDs are much too bright, adding to the current draw. There are two PCB pads labeled "switch", what are they for? They are not for the switch I suggest, because it works without connecting those two pads.

I like to build raspberry pi systems but I'm not the best at coding. I tried an adafruit battery meter but didn't realize their jst plugs are wired backwards to most lithium batteries so I accidentally burned the chip. After spending 45 dollars on adafruit stuff and wrecking it I didn't have the heart to order another one, so I just ordered these. I wired it directly into my power delivery wires and added a momentary button. It gives me battery level at a glance without powering on the system. It takes a while to learn how to read it within your system, for instance I am using a 10,000 mah lipo and the battery level will read (2) when the output drops below what the pi can use, but this is probably just the pi's power draw not a limit of the indicator. I have fully drained the battery and seen the indicator show 1 unit and zero and I believe it is accurate, but in my application the battery has to be at 2 or above to power the computer. anyways it was awesome to find a simple solution like this instead of relying on expensive specialty chips that require a lot of code. I love that I can glance at the power level without powering on the computer.

Received these today. 3 out of 4 worked normally. One of them wouldn't illuminate the lowest bar. I couldn't find a way to contact the seller to get it replaced, and it didn't seem worth returning all of them for just one bad item. I wish there was an option to contact the seller directly. If it's there I'm unable to find it.

Nice battery indicators. Probably consume more power than I'd like so I put them on a switch.

I used this as a battery meter for a project. Bright LEDs and easy to wire. 5 stars

Works at intended and very bright. I took off 1 star because of miss-leading picture described that this 3s unit can measure 1s. It DOES NOT work with 1s. Plus, on 3s units that I received, there are six holes of (+) and (-) combined in which 2 holes are not labeled and other 4 do. I've tried different combination but it does not work with 1s. Only the parameter lighted up red, no indicator bars shows. Again, seller should delete that picture that shows it can measure 1s or 3s to avoid miss-leading for other customers in the future.

Very Good Deal