Simple battery voltage monitor?

I am looking for a simple, small battery level monitor for custom hosts. Similar to this:

3.5-7V RX Battery Voltage Level LED Indicator | eBay

This one is for 6v racing packs, I think. $5 is a good target for something like this.

I may get this one, but it's a tad large and for a single cell:

5 LED Lithium Battery Voltage Indicator Board With Low Voltage Warning | eBay

RHD had a voltage LED build in the host in one of his Ancient builds. I don't know which one, you have to look for yourself

What you want is a "1s Lipo" battery meter. Just the meter without the low voltage alarm. (those look too big too me)

I have a custom build with one just like the one RHD used in his build.

I think that host is the first one Ancient Light by RHD if you are trying to search for it.

This one is doggone cheap, but intended for NiCd or NiMH 4 and 5 cell packs:

RC Model 7 LED Battery Voltage Indicator Monitor Car | eBay

That said, it has a switch for 4.8 or 6v operation. Think I'll get one and see if I can mod it for 7.4 and/or 3.7v.

That may work. It's certainly affordable enough. Just watch the size if you are planning to use it in a handheld laser. I didn't check the deminisions but it looked a little chunky.

I like the style of the little lipo units. They are pretty small and just plain sexy.

Here are a couple of snaps of the backend of a very special "not quite as ancient light" that was built for me. Big bright 635nm out the front, internal battery with charging port and built in battery monitor. Yep the battery needs to be charged.




You can find the battery monitors on eBay for not much more then the other one you linked. Btw: That is originally a 2 C cell host to give you an idea of size.

Yeah, there are volt meters out there for $3, but they generally need at least 4.5V or 3.3V to measure the battery voltage directly since they use the battery voltage to power themselves, too.

Yes - good point. There are, however, versions which have a third wire and will measure 0-100V. They are not much if any more expensive. The cheapest seem to hover around $4-$5. Now, if I could just find a curved display that would flush-mount with the host. I plan to put them in the tailcap of larger builds or anywhere else I can find a sizable flat spot.

Why not use something such as a LM3914? Even 10 LED's is gonna be easier to mount in a host than a full 7seg display, and you'd still get meaningful battery levels.

Even more useful, perhaps, is a current monitor. These are basically the same thing, measuring (I assume) voltage across a known resistance (the shunt). I don't know if they are modifiable for, say, 1 amp, but I guess you could divide by 10.

0.36" DC Digital Ammeter 10A Red LED Panel Amp Meter Electric Current Meter | eBay