LiPro Balance Charger

LIPRO BALANCE CHARGEREvery time I see a video about charging or testing batteries, I tend to see one of these shiny blue units (or similar) – so I thought it was about time I got one! 

The LiPro Balance Charger (or rather, a clone as we will see later) is pocket sized and has an input socket on the left… it takes from 11v to 18v input… and trust me it objects loudly if you put in a higher voltage as I did – beeps like crazy – but then that’s better than blowing up, any day.

I have lots of Lithium and other types of batteries lying around and some of the claims for them are bordering on the ridiculous – and I’ve always thought, wouldn’t it be nice to actually be able to CHECK the claims – and of course another battery charger never goes to waste. Read on…













The LiPro Balance charger can not only charge single Lithium batteries but also 2,3,4,5 or 6 at one time. The lead for multi-cell charging includes a temperature sensor. Not only that but the unit charges NiCD and NiMH as well. It even charges what they call Acid-Lead batteries though from what I can see this is limited to 6v. I did find the lead fittings a bit odd – maybe meant for radio control – but hey – that’s what SNIPS are for!!!

Instructions come in perfectly good English and it took me, what, 3 minutes to figure out how to charge a Lithium battery and start the ball rolling. There’s a flow chart that makes it all look surprisingly simple.  I wish others would do that.

You do need external power and external connectors for the battery or batteries. This unit doesn’t open up or anything.

I plugged in a pretty charged Lithium battery and about 15 minute later there was a loud beep and the 2-line LCD (blue background, white text) reported that the battery was fully charged (it was pretty full to start with).  The unit will charge from 0.1 to 6 amps (well, if your power supply is up to it) and discharge at up to 2 amps.

I decided to put a handy Ultrafire 3,000maH fully charged battery to the test.

For discharging, at least in the case of a Lithium Ion battery you have full control over the point at which you STOP discharging – I chose 3v and for the discharge current – I chose 1 amp because life is short. Again you can select how many cells etc. All very simple really, but then that’s how it should be.

The unit has a backlight which turns LOW after a while. Personally, given that this may well be using a reasonable amount of electricity – and thinking about the current that entails – I’m not sure I see why they felt the need to dim the backlight… could get annoying….  there are some settings but according to the chart, backlight timeout isn’t one of them.

LiPro Balance Charger

Sure enough I pressed start and the Ultrafire battery started to discharge at 1 amp. If the fully charged (and pre-used) battery had the capacity claimed – I would expect it to be complete in three hours.

The experiment was short-lived as the battery voltage quickly began to go downhill. After 15 minutes at 1 amp, the battery was down to 3 volts and the charger cut out- beeping in the process. The battery then recovered to 3.6v

After recharging again (didn’t take too long – I don’t think it is charge that is the problem I think it is more like the battery impedance) I tried again at 0.5 amps. Well, this time it lasted longer but not THAT much longer – and certainly no-where near an hour never mind 3 hours (or 6 hours at 0.5 amps).

The question we have to ask is – is the charger falsely reporting the problem – or is the battery utter rubbish.  Given the comments I’ve seen about Ultrafire batteries in the past and given that I’ve seen this charger unit used ALL OVER the place… I think I know where I’d put my money in a bet. I’m going to do some more testing before putting this battery up against the wall to be shot at dawn.

Oh, ignore the settings in the photo – I took that before I actually started testing – I set the unit to LiIO (Lithium Ion)…  I LIKE IT!!!

In the coming days I will try other batteries and report back. Right now – this is my second eye-opener of the week. It really is simple to use – and my wife who is CONSTANTLY on at me to get rechargeables and complaining they don’t last enough – well, I think she is going to LOVE this.

In response to a request from reader ROY I checked this unit – apparently the originals have a hologram on the bottom – so this is not an original (well, at least, there’s no hologram on the bottom) which of course may raise questions about accuracy. Well, I’ve checked with my best meter – and at 3v, the accuracy is only 1.73% out… whether that is at the charger end or my meter end will have to wait for my precision reference board to turn up to resolve. Assuming it is the charger, I would have thought that is well within acceptable limits

The follow-up

After wasting a lot of time with that Ultrafire battery, I decided to try a fully charged battery from an old laptop – one I know works just fine.  The picture here is very different.

I plugged in the LiPro clone (as we will now call it as it does not have the apparently necessary hologram on the underside) and set to discharge at 1 amp. I also set the cut-off voltage to 3v3 as, reading up on the subject it would appear there is not THAT much to be gained by going all the way down to 3v3.  Fair enough. I set the unit to discharge and set it running.

The battery voltage very rapidly went down from 4.1v to 3.9v – but then stayed pretty much static for several minutes – THAT’S more like it.  As I was sitting at my desk anyway, I figured I’d leave it running.   The display backlight went off as discussed earlier but I realised you can press ENTER once and it will come back on without actually affecting anything. 

6 minutes in and the battery was sitting at 3.88v. The battery was cold and the charge unit was…. almost cold.

By 15 minutes – the battery was at 3.77v and almost cold while the unit itself warm-ish (sorry, left my IR temperature meter in Spain).

At  30 minutes – the battery was 3.63v and again still almost cold, so no worries there. I would describe the unit as being warm, not hot, but based on this – I would not want to set twice that current without a fan  – bearing in mind I’m in an office at 21c – and not in Spain at 29c!  But 1 amp is just fine for discharge testing IMHO.

At 60 minutes – the battery was at 3.44v, still almost cold, the unit temperature was holding.

At 90 minutes – the alarm sounded. 3.3v had been reached and charging stopped. At this point the battery had recovered to 3.57 – but then – it would.

But the story doesn’t end there – At this point, just for the sake of it I wondered how much extra I could get if the unit was just discharging at 0.5A.   And of course this is the beauty of such a unit  -you can do ALL sorts of experiments if you are that way inclined. I set the discharge to 0.5A and started – sure enough the battery voltage dropped almost immediately to 3.44v but seemed to hold. I left it running while I got on with other stuff. After  40 minutes it gave up but it does show you get extra capacity just by discharging at a lower rate.  Interesting!!!

If you’ve used this unit before – please COMMENT. If you’ve used Ultrafire batteries before – please COMMENT.

For other chargers and related see this


17 thoughts on “LiPro Balance Charger

  1. I need the circuit diagram, component list as well as the full detailed information of this project. Being an engineering student i want to study it. if some one can help me please reply me at ‘’
    thanks in advance.

  2. Discovered once cheali-charger firmware (on github) for these chargers. Flashed on mine cheap ebay charger. What is good it is possible to calibrate readings and it shows internal resistance of element charging. Though success might vary depending on MCU in device (seems there are variants which might not work).

  3. Hi Pete
    If the web site has a comment field, see what other purchasers say
    about capacity, it is quite common (aliexpress). As a rule of thumb,
    if a 18650 is claimed over 3000mah, unless it is Japanese or korean
    it is a lie. I bought an Opus 3100 for battery charging/testing,,
    a great piece of kit. The largest true capacity (18650) is ~3500 mah
    Many from dead laptops are 2200

  4. Sometime ago I removed some Panasonic batteries from a DELL battery pack that the laptop computer refused to use/charge. These batteries had something wrong and got very hot when charging. Since then I bought a temperature sensor I always use when charging Li-Ion batteries with my Turningy charger (Similar to the one you bought). The charger has a port to connect this sensor and if the batteries get hot the charger stops it process.

    Li-Ion batteries should never get hot when charging. That is very dangerous. The batteries could vent with fire and burn your house. You do well keeping an eye on Li-Ion batteries when charging.

  5. Ref. The comments about rogue cells and cloned kit, and the difficulty in ensuring you get the right kit, I would never buy stuff like this from anyone but a reputable supplier. Sorry, but the savings in buying dodgy kit direct from China are FAR outweighed by the probability that the batteries won’t work, or, as mentioned above, explode and burn your house down … the risk isn’t worth it.

    Ref. Comments on Ultrafire – just Google the name …. dozens of hits on how bad they are!

    I have a friend who has only just learned not to buy Chinese 18650 batteries after finding out they have a tenth of the capacity stated, if you are lucky.

    Finally, apologies for stating the obvious, but the capacity of these things is stated at 0.2C discharge so if you discharge faster, you won’t get the stated capacity, but if you discharge slower, you will get more – the first Law of batteries. Normal battery capacity is usually stated at 0.1C, but then 18650s aren’t normal, are they. Again, normal batteries data sheets show a discharge curve highlighting this effect, but I couldn’t find an 18650 data sheet with a curve for love nor money.

    1. So first comments John “dodgy kit from China” – that’s not fair – MANY European suppliers – and American – buy stuff in from China – mark it up and resell while not adding much if anything so I don’t go along with that necessarily. I get really annoyed when I see Ebay ads – big British flag
      – and all they’re doing is charging 3 times as much for something I know for a fact they just bought in from China… I think we should just settle on saying that the Chinese build to a price – and if you pay peanuts…..

      Secondly – this unit – the instructions are quite clear – don’t use unattended. Can’t say fairer than that. I checked the voltage readings – they seem accurate. I guess I should open it up and give it a look inside. Of more concern to me is – how well does it work – next stop I’ll try a decent battery. The Ultrafire is going in the bin, regardless.

      On Ultrafire – I have to agree. I bought two of these when I didn’t know a Lithium battery from a hole in the ground – problem is – who do you trust? Yes, I think Aidan had a 18650 claiming to be 4900maH and on test got something like 900maH out of it!!! Really, we need a naming and shaming campaign.

      On your final point – I’m with you – I know about the stated curves – reality is though – almost EVERY (just as an example, nothing more) PI power supply developer out there uses these batteries to power Pis – and they need an AMP. Most TORCH manufacturers use them – and the larger torches need an amp or even more. So despite what the STATED discharge is – everyone uses them for a LOT more and expects them to perform.

      Now, here’s where I get into shaky ground, but I’ll do it anyway. TESLA both charge and discharge the batteries at WAY more than any levels we’re talking here yet get the capacity and claimed battery life (well current claims anyway) are up to 30 years… so we need clarification – but again – who do you believe.

      1. HAH.. even more interesting – I’ve just realised I have TWO Ultrafire batteries – completely different imagery, one says 3000maH (it isn’t) and the other says 4200maH.

        In the bin.

      2. about ultrafire… take a look… i’ve personally seen one of this, EXACTLY containing what you’ll see in video… threw them in the bin ASAP…

        open yours and take a look inside…

        1. Mine are red – and both different… but then if not from Ebay, how do you know which reasonably priced dealers have been duped when buying in cells!!!

  6. Peter, could you provide a link to the precision voltage reference please. I did some battery testing using the dummy load which you are awaiting. Using that dummy load I was able to get very reliable results measured with my Siglent, Thurlby and Fluke multi meters. Very pleased to say that some Li-on batteries suggested by one of your readers way back (Panasonic) performed to specification. With the dummy load testing is as per the Imax, discharging at a chosen rate to a preset voltage then stop. INA219 monitoring current/voltage linked to ESP8266, UDP to MegunoLink software on PC provided graph of the process, stores the result and anything else you want. Really nice and useful testing.

    1. Hi Bob.. Rather than provide a link to something I’ve not even seen first hand, if you care to hang on – when it actually turns UP – I’ll do a short writeup with link. I’m getting concerned now after reading all about this I checked all my meters and they are a little different – I really need to know which is the most accurate . I won’t bin the rest but I’ll put a label on the back with a correction factor which will KIND of do for voltage at least… unless they have a calibration option – the cheaper ones won’t, of course. I’m going to do more with those INA219 but when my resistors turn up – it could be that the INA3221 turns out to be a winner. Time will tell.

  7. Pete,

    I’ve got one of those iMax B6 chargers as well – an Asian clone with no hologram label on the back – but it works OK. The genuine iMax B6 has a nice hologram label on the back to prove it’s genuine.

    The only issue I’ve had is that the voltage readings made by the device are a “bit rough”. The genuine iMax B6 device has a way of getting into a hidden menu to calibrate the charge and discharge voltages, but no such menu setting is available on clone charger.

    Once you get the voltages calibrated, that apparently also addresses the charge/discharge current calibration.

    I killed a brand new unprotected NCR branded Li Ion 18650 by over-discharging it due to the discharge cutoff voltage being out by about 25%. Very hot – nearly a fire.

    I now use a multimeter to keep track of the charge and discharge voltages – and I NEVER leave a battery charging with this charger unsupervised. It is a brilliant charger design, and I plan to replace mine with a genuine iMax B6, just as soon as I can work out how to ensure that I’m actually buying a genuine one over the Internet.

    If your charger is a genuine iMax unit, do a Google on “how to calibrate an imax b6” as there are heaps of links, and apparently even the genuine units can benefit from calibrating when you start using them.



    1. Thanks for that useful feedback, Roy. When I get back into my office I will check with my meter and report back. The whole thing about accuracy came to the foreground this week when I watched a video comparing various meters and showing up the variation between them. Accordingly I have ordered a precision voltage reference.

    2. Right – some feedback for you (and everyone else). The unit is indeed a Chinese clone – well, it’s a clone anyway, as it does not have the hologram on the back.

      However, two things – according to my most expensive (and hopefully, most accurate) meter (still waiting for my precision voltage reference to turn up) – the unit when claiming the battery is at 3.00 volts is 1.73% out (i.e. the actual voltage is higher). IMHO that is an acceptable level of deviation.

      What is not acceptable is the failure of the battery to handle the discharge. I’m going to charge the battery via a different route just to be sure.

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