DJI Batteries Is there a device that will measure the battery Voltage

[Rgrimard]

I have the DJI Mavic Air-2 and the Mini-2. Several of my Fixed Wing LIPO batteries Voltage can me
measured by a small Led device that measures how much voltage is each battery, now I know which LIPO needs
to be charged. Why doesn't DJI make a tool that has an LED read out to tell me Which of the 3 batteries needs
charging??? As far as I know there is none? Any thoughts on this ??

 

[Deleted member 103366]

For differing batteries your best bet is likely to be a cheap multimeter. You'd need to have the battery pinouts but they are readily available.
Being honest, for simple tasks such as this, a less than $20 digital multimeter (DMM) with fine probes is likely to be perfectly adequate.
I don't think that I would bother with a cheap analogue meter but a £7 throw-in-your-tool-bag DMM is, for such work, as good as a £300 good DMM and you need not be overly bothered about its safety.

 

[MAvic_South_Oz]

If you have a flymore battery adapter, if one is made for your model, or purchase one, you could perhaps mod a USB cord to read the volts.
Either by multi meter or rig up a small led readout volts gauge.

Mind you, if any battery is below 100%, apart from a partial charge one from a flight that session, it shouldn’t be flown in anyway.
They should always be recharged to 100% for flight.

The battery leds (and a single press) are more than enough to know what batteries need charging after flight, or ones that may have drained somewhat in mid term storage, or if it can be left to finish self discharge if partially flown.

 

[Deleted member 103366]

you could perhaps mod a USB cord to read the volts.

no need to modify a cable, there are the likes of these USB Tester Voltmeter Ammeter Digital LCD Voltage Monitor Current Meter Capa W3C9 4894864817319 | eBay
and other versions

With my rigid versions i.e. there is no cable, the most annoying problem is that it is surprising how many times the display ends up facing away from me. I also find that the connectors get a bit temperamental if they are used a lot which is why I gave the link to a cabled version, it might be a bit more robust.

 

[MAvic_South_Oz]

no need to modify a cable, there are the likes of these USB Tester Voltmeter Ammeter Digital LCD Voltage Monitor Current Meter Capa W3C9 4894864817319 | eBay
and other versions

Well that’s a very easy option, a battery USB adapter (if available for his drone) can be very handy for the OPs needs then.

 

[Rgrimard]

Ok....so the answer is there is no such device made specifically for the DJI Batteries that
you can just pop onto the Pins and see the Voltage on those Cells.
Thanks to you all for your Comments and suggestions. It saved me many hours of Searching
for something that does not Exist and would not fit into my Flight Bag (or Case)....appreciate the feed
back....Ron

 

[MAvic_South_Oz]

Ok....so the answer is there is no such device made specifically for the DJI Batteries that
you can just pop onto the Pins and see the Voltage on those Cells.
Thanks to you all for your Comments and suggestions. It saved me many hours of Searching
for something that does not Exist and would not fit into my Flight Bag (or Case)....appreciate the feed
back....Ron

Nothing specific because it’s not particularly needed by pilots of DJI drones.
Do you know how big the DJI flymore battery adapters are ?
If one was made for your drone model battery, which you failed to mention, that little USB corded gauge @PhiliusFoggg linked could be left connected to it and be very compact.

 

[Deleted member 103366]

I have the memory of someone making one for the mini, it had other functions too but it wasn't a commercial device and I think it used adrino? computer. I think they published the information necessary to build it and I would have liked to build one as I thought the other functiions were useful, but following the mentioned information was beyond me.

You could make something using a simple LED voltmeter such as

but you'd have to make up suitable plugs etc. to mate with the battery terminals or make up probes and I think it would be more trouble than it is worth when a cheap DMM would suffice and offer other measurement capabilities as well.

 

[Deleted member 103366]

Ahhhhhhh found the bookmark have a look at


Mavic Mini battery info

 

[slup]

...Several of my Fixed Wing LIPO batteries Voltage can me measured by a small Led device that measures how much voltage is each battery... Why doesn't DJI make a tool that has an LED read out to tell me which of the 3 batteries needs
charging???

But you have ... the Air 2 have 4 led's directly on the battery & the mini 2 you either use the craft itself or the charging hub which both have led indicators.

DJI have since long considered a direct voltage readout unnecessary for people in in general ... this as the battery have a BMS chip which a general LiPo pack doesn't have. And I agree with them, it's plenty enough with the four led's, each 25% & a percentage shown in the app during flight + low battery RTH + forced low battery auto landing ... should be easy to know which one to charge or discharge to storage after a flight session.

The only flaw they did was to not include something to bring them to storage (3,7-3,8v/cell) at will ... this as the auto discharge takes way too long in days counted. But the led rule for storage is between 1 solid+1 blinking to 2 solid+1 blinking.

It's a very different battery scenario with your fixed wings ... there you don't have any BMS chip that prevents you from over charge or over discharge ... & usually we take out as much as possible to gain flight time, but we know where the limits are ... no lower than 3,3-3,5v/cell ... that is equivalent to a DJI percentage of below 5%, we usually never strain DJI batteries as we do with wing or quad batteries. So for general LiPo packs a cell voltage readout is necessary as we are the BMS ourselves.

So no need to over complicate the use of DJI batteries, always charge them full before each flight session (this mainly to get all cells properly balanced), then don't bring them down to less than 15% on a regular basis (they are expensive so it's valid to treat them a bit better than the general LiPo pack). And after use see to that they gets stored away on 3,7-3,8v/cell (2 solid leds is quite spot on for 3,8v/cell).

 

[Deleted member 103366]

But you have ... the Air 2 have 4 led's directly on the battery & the mini 2 you either use the craft itself or the charging hub which both have led indicators.

I think it comes down to some people, myself included, like, or would prefer, to see numbers rather than segmented etc. displays.
I incorporated/added an LED voltmeter into the battery tray of a DSLR two battery battery-grip.

 

[JMC3]

This reminds me of the days auto manufactures used blinking red lights on the dash instead of real electrical and oil gauges

 

[Kilrah]

Why doesn't DJI make a tool that has an LED read out to tell me Which of the 3 batteries needs
charging???

Because it's already built into each battery (or the drone in the minis)?

 

[eljimb0]

I think if there were individual pins on the battery box that went to each cell it would be great. If you have a pack that has one sleepy cell that could be accessed without hacking open the case ....thousands of battery packs could be saved. But there is no money to be made by saving battery packs.

 

[Heretik]

I have the DJI Mavic Air-2 and the Mini-2. Several of my Fixed Wing LIPO batteries Voltage can me
measured by a small Led device that measures how much voltage is each battery, now I know which LIPO needs
to be charged. Why doesn't DJI make a tool that has an LED read out to tell me Which of the 3 batteries needs
charging??? As far as I know there is none? Any thoughts on this ??

I dont know if it has been written about? Hanatora Charger for MA2.

4 batteries charged near simultaneously; cycling from one to the next at about 5-10 second intervals. Individually reads voltage and amperage draw of each as they cycle through.
IMO very fast charger at 13.2V / 2A and fan cooled. I usually see it starting at 2.2A. And when battery reaches full charge it gradually but steadily reduces amperage to 0.1 before shutting off.

Have been using it for 8 months post flights, and on bi-monthly maintenance regimen. Always topping off batteries <24 hrs before flights.