Multistar High Capacity 6S 16000mAh

I don't balance so much as I have to bulk charge then balance with my 50w SkyRC)

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But if you are "breaking" your packs to charge,you are not really bulk charging.
I.M.O., disrupting the serial connections is the absolute worst thing to be doing, especially when there are so many 50.4V charging solutions from Mean Well clones($30 plus shipping) to the industrial quality HGL 320 series (Mean Well LED power supply.)
All you need to do is to have the main power connector and the balance taps accessible on the bike.
My super fast charging HGL 320 and 4 Battery Medics:

My Mean Well doesn't continuiously start and stop to read cell values like balance chargers do. 300 plus Watts the moment it's connected.
Two 6S 5000 mAh bricks(12S serial pack) takes about 30 minutes from 3.8V to 4.10 V.;

My feeling is, make things easy on yourself so checking and balancing isn't a chore, do it every ride and you will get those 300 plus service cycles. And by not breaking the pack, the cell values will stay more stabil.

motomech said:

I don't balance so much as I have to bulk charge then balance with my 50w SkyRC)

Click to expand...

But if you are "breaking" your packs to charge,you are not really bulk charging.
I.M.O., disrupting the serial connections is the absolute worst thing to be doing, especially when there are so many 50.4V charging solutions from Mean Well clones($30 plus shipping) to the industrial quality HGL 320 series (Mean Well LED power supply.)

Click to expand...

I am not sure what you mean by breaking packs? I had 2 6s packs that run in series on the bike, to 'bulk' charge - I plug the main outputs (2) in parallel into the charger and charge, not balance up to the minimum I can (50.2v) then I had to remove them from my bags so I can reach the balance plugs and plug in the parallel balance leads + main parallel leads to my small but trustworthy iMax B6 balance charger to finish it off.

Are you saying there is a reason that they should always stay connected in series, what specifically makes it the absolute worst?
On a side note I did get 3 battery medics, do you keep them attached while charging and they balance as you go? or leave them on overnight also or all the time?
It would make it even easier to charge if I didn't have to unplug from serial to parallel every charge may check out those HGL's...

Ok, correct me if I'm wrong, but you are using one or two RC chargers, right?
Since all these except twp very expensive ones only go as high as 10S and most are 6S max., you have to dis-connect your 12S string(Serial)to charge at 6S. That is breaking the pack.
Or, do you have something that charges to 12S (50.4V)?

Most of the time, at the end of the charge cycle, the cell values are only .02 or .03 Volts off and I don't worry about those. Any more than that and I will clip a BM on each offending brick and pull it down so I have an acceptable avg. across all cells on all the bricks. This usually only takes a few minutes.
Right now, I have new Lipo, 4) bricks of 6S/10Ah, or a pack of 12S/20Ah.(2S/2P) and the cells are straying quite a bit.
I'm keeping my discharges shallow, but even so, I will ck. the cell values halfway or so thru the charge cycle, and if they are off, I will start the BM's and turn the charging Amps down to 2 or 3A.
Lipo is funny and it's like it has a memory and as the cycles go by, the cells "learn" to work together and eventually fall in "lock-step".
The main reason I don't like to dis-connect anything on the pack except the main power leads is because it unsettles the cells. Maybe just a little bit, but it kinds of adds up.
Lipo likes routine and I even try and keep the discharge range about the same, in my case 4,10V down to 3.8V. Since I have so much battery capacity, that's pretty easy to do.
There are balance lead extension(See my pic)that make it easier to reach the taps. And to keep the number of BM's down, there are paralelling and splicing options. Like you could splice your 4s + 4S + 4S leads into 6S + 6S. so you would only need two BM's instead of 3. Or, you could parallel two 4S bricks so you would have one BM on two 4S bricks. But you need to be quite sure of what you are doing before attemping this. Even paralleling leads can be tricky. If the cells to be paralleled are not exactly the same value, current will rush from the high cells to the lower cells and vaporise the balance lead.

Nope, it is as you say, I charge at 6s and discharge @ 12s (and planed to charge 3x4s in parallel with the new kit)
I just hadn't heard or read anyone (whom accepts HK Lipo with no BMS as acceptable) suggesting this isn't a good way to do it, or that it is the Worst, as you said, so wondered on the specific reasons.

I had a look at using the 50v LED power supplies and it looks more risky (eg: more careful monitoring req.) than paralleling on a 6s charger, as it doesn't know how to ramp down amps at the end so you have to watch it closely? (still reading up on this)
Thinking i'd be better with a BMSbattery charger instead + BM's for that, will lose voltage adjustment that your setup has though
With the new setup I'll have ordered 3 BM's + a pack of 4s balance extensions so that will help me measure really quickly and at least fix the main cause of my early cell failure.

For what it's worth my packs were self balancing for approx 150 cycles using that charge method, never needed a balance when I checked (but I did anyway while I had them out)

Still wondering if I should cough up $50 for a BMS, as my 48v controller LVC is 40v which is too low, wish AU had better suppliers for such things

menvert said:

....
I had a look at using the 50v LED power supplies and it looks more risky (eg: more careful monitoring req.) than paralleling on a 6s charger, as it doesn't know how to ramp down amps at the end so you have to watch it closely? .....

Click to expand...

..??..most of thr LED powerSupplies and Meanwell clones do ramp down and have a typical CC/CV charge profile.
..but of course no balancing ability.

Yup, The MW HLG has CV/CC. As it approaches the pre-set End of Charge Voltage, the current ramps down to next to nothing.
Once it reaches the E. of C. V., it stops charging.
The unit also has;
thermal protection
Polarity protection
Is fully potted
Weather proof
needs no power supply, of course.
and has a 5 year warrenty.

I added a voltmeter, a high cell alarm and a timer to shut the unit off.
The quality is way beyond the typical toy charger or BMS Battery crap chargers and having gone thru a Thunder 1220 and a Hyperion 1420, it's nice to know I won't have to buy another charger.
Best $130 I've spent on Ebiking so far.
These days, It seems I'm getting hammered a lot for not having a BMS(although I've always stipulated no BMS is only for packs 2P or less).
Probably should just keep my mouth shut and let people do it their way.

My trike is due for a new pack, 100v ( 24 cell ) and needs to dish out 80 amps .. .. the big multistar 20ah packs are tempting to make clean wiring.. ..... but i've had good luck with the 5ah 20~25C turnigy packs.. not so much with the zippy that tend to die after a few years, regardless of cycle count.

will the multistart cope with real 5C discharge rates ?

motomech said:

Yup, The MW HLG has CV/CC. As it approaches the pre-set End of Charge Voltage, the current ramps down to next to nothing.
Once it reaches the E. of C. V., it stops charging.
The unit also has;
thermal protection
Polarity protection
Is fully potted
Weather proof
needs no power supply, of course.
and has a 5 year warrenty.

I added a voltmeter, a high cell alarm and a timer to shut the unit off.
The quality is way beyond the typical toy charger or BMS Battery crap chargers and having gone thru a Thunder 1220 and a Hyperion 1420, it's nice to know I won't have to buy another charger.
Best $130 I've spent on Ebiking so far.
These days, It seems I'm getting hammered a lot for not having a BMS(although I've always stipulated no BMS is only for packs 2P or less).
Probably should just keep my mouth shut and let people do it their way.

Click to expand...

Yeah sounds good, and I'll probably go that way if I get a BMS, but right now it's gonna cost me more than the batteries for a genuine one and only 5.95A, when I already have an pricey charger (but max 8s)
Does any Power supply that states CV/CC automatically ramp down at the end too?

Ypedal said:

My trike is due for a new pack, 100v ( 24 cell ) and needs to dish out 80 amps .. .. the big multistar 20ah packs are tempting to make clean wiring.. ..... but i've had good luck with the 5ah 20~25C turnigy packs.. not so much with the zippy that tend to die after a few years, regardless of cycle count.

will the multistart cope with real 5C discharge rates ?

Click to expand...

The consensus seems to be a little under 2C continuous (25A for the 16Ah packs) so I don't see it as a good choice for 80 A on 20Ah pack)

I have got 6x Multistars 6S 10Ah and discharged the pack with my HK Accucell:


Volts after 1st discharge:
Σ: 19,92
3,50 - 3,22 - 3,18 - 3,21 - 3,13 - 3,67

how bad is that?

Darowi said:

I have got 6x Multistars 6S 10Ah and discharged the pack with my HK Accucell:


Volts after 1st discharge:
Σ: 19,92
3,50 - 3,22 - 3,18 - 3,21 - 3,13 - 3,67

how bad is that?

Click to expand...

Aren't those stats highly dependent on how many watts you drew down?... as in If you already got a full 10Ah at that point, then it could indicate 2 cells that are over spec?
That and are you getting a 2nd opinion on the voltages?... my Turnigy Mega 1000W Charger randomly over reads cells, and over charges if you balance in that situation
On a related note, I got my new batteries and gear, but not too happy with my HK battery medics, only 1/3 have reasonably accurate reads (within 0.01v) & one is out 0.04v from 1 cell to another on actually balanced cells

The Blue ones were accurate enough, but the blacks ones(which seem to be all that is avail. these days)are junk.
Of the 4 black ones I have, only one matches my blue ones in values
Still, Battery Medics are about averages, not super accuracy.
If one or more BM's are being used and are close to each other(.02 to .03V), they can still be used to balance.
I wonder if we are being too picky about getting the cells exactly the same and I suspect that differences or .003V or .004V are not that critical.
But then again, I have found that if the cell values of two bricks are <.05V in difference, and the main power cables are paralleled, I can get an in-rush spark.

motomech said:

The Blue ones were accurate enough, but the blacks ones(which seem to be all that is avail. these days)are junk.
Of the 4 black ones I have, only one matches my blue ones in values
Still, Battery Medics are about averages, not super accuracy.
If one or more BM's are being used and are close to each other(.002 to .003V), they can still be used to balance.
I wonder if we are being too picky about getting the cells exactly the same and I suspect that differences or .003V or .004V are not that critical.
But then again, I have found that if the cell values of two bricks are <.005V in difference, and the main power cables are paralleled, I can get an in-rush spark.

Click to expand...

Yeah they will still be great for fast 'ball park' checking of my cells, glad I am not reliant on them for balancing though, mine only measure to the nearest .01v do yours go to .001v?



Only once I fully charged did I get one of the BM'ss out by the .04v
When I measured with volt meter all the 3 4s 16Ah bricks were well balanced upon arrival, within .01v, one brick took ages for the first balance though, 2nd cell took a lot to come up to fully charged voltage, so will keep a close look, may be an over capacity cell or something worse, but sorted my back rack so I can easily check/balance & even remove the pack easily, so no more excuses re: not balancing often.

EDIT: I don't suppose anyone knows about the Turnigy Deluxe ones? http://www.hobbyking.com/hobbyking/store/__26136__Turnigy_DLUX_LIPO_Battery_Cell_Display_and_Balancer_2S_6S_.html

menvert said:

motomech said:

EDIT: I don't suppose anyone knows about the Turnigy Deluxe ones? http://www.hobbyking.com/hobbyking/store/__26136__Turnigy_DLUX_LIPO_Battery_Cell_Display_and_Balancer_2S_6S_.html

Click to expand...

Click to expand...

I have one and it seems a lot more accurate than the black ones.
The individual cell voltages never add up to the total at the bottom on my black ones.
I like the fact that the deluxe also tells you the percentage of capacity in the battery as well.

Darowi said:

I have got 6x Multistars 6S 10Ah and discharged the pack with my HK Accucell:
Volts after 1st discharge:
Σ: 19,92
3,50 - 3,22 - 3,18 - 3,21 - 3,13 - 3,67
how bad is that?

Click to expand...

For comparison I did an endurance test on my 3x 4s 16Ah and yes, just below 3.6v under load they fall off the cliff really fast I was riding @ 43v then 500m later 42v... I limped home to about 41.6v at rest with these cell voltages;
3.44,3.45,3.47,3.53,3.45,3.61,3.64,3.41,3.40,3.37,3.46,3.37 - which I think is fairly typical given cell or brick capacity is rarely 100% matched

I certainly wouldn't want to take these down to 3.2 as they are already spent and seconds away from going below minimum at that point, so I agree 3.5 LVC under load would usually save the battery, lower and there is a real risk of going too low.
I got 47k range and my commute is 36k so I am getting a good 80% DoD.
I won't be taking them that low again it was just for testing, and they took a lot to balance after that. Sorry I don't have a Watt Meter and my charger overvalues the watts by about 20%

My most accurate BM did a good job helping balance too, very convenient, though might get the Deluxe one one day

Ypedal said:

My trike is due for a new pack, 100v ( 24 cell ) and needs to dish out 80 amps .. .. the big multistar 20ah packs are tempting to make clean wiring.. ..... but i've had good luck with the 5ah 20~25C turnigy packs.. not so much with the zippy that tend to die after a few years, regardless of cycle count.

will the multistart cope with real 5C discharge rates ?

Click to expand...

Mine get warm (like halfway through a mug of tea warm) drawing 40-45amps from the 20ah packs for any longer than ten mins. But they are in an unventilated bag stacked up 3 high. So 10 degrees centigrade ambient up to maybe 20ish.

18 miles into a ride at 3.8v resting or 3.7v under load I lost half power. Like something dialled it back. I stopped for 5 minutes and it came back. No idea if that was the controller or batteries.

Didnt icecube or someone suggest 3c is a good max. Your right though the simplicity is great once you land packs with no dud cells and I am finally able to bulk charge to 4.17v.

menvert said:

motomech said:

The Blue ones were accurate enough, but the blacks ones(which seem to be all that is avail. these days)are junk.
Of the 4 black ones I have, only one matches my blue ones in values
Still, Battery Medics are about averages, not super accuracy.
If one or more BM's are being used and are close to each other(.002 to .003V), they can still be used to balance.
I wonder if we are being too picky about getting the cells exactly the same and I suspect that differences or .003V or .004V are not that critical.
But then again, I have found that if the cell values of two bricks are <.005V in difference, and the main power cables are paralleled, I can get an in-rush spark.

Click to expand...

Yeah they will still be great for fast 'ball park' checking of my cells, glad I am not reliant on them for balancing though, mine only measure to the nearest .01v do yours go to .001v?



Only once I fully charged did I get one of the BM'ss out by the .04v
When I measured with volt meter all the 3 4s 16Ah bricks were well balanced upon arrival, within .01v, one brick took ages for the first balance though, 2nd cell took a lot to come up to fully charged voltage, so will keep a close look, may be an over capacity cell or something worse, but sorted my back rack so I can easily check/balance & even remove the pack easily, so no more excuses re: not balancing often.

EDIT: I don't suppose anyone knows about the Turnigy Deluxe ones? http://www.hobbyking.com/hobbyking/store/__26136__Turnigy_DLUX_LIPO_Battery_Cell_Display_and_Balancer_2S_6S_.html

Click to expand...

mine only measure to the nearest .01v do yours go to .001v?

Click to expand...

Oops, my bad, I meant hundreds of an inch, not thousands(POST EDITED).
FYI. With one of the blues ones I have, the discharge/balance values can be set every .01V. For example, 3.80V, 3.81V, 3.82V, etc. It's great! The other two blues ones can be set every .05V, 3.8V, 3.85V, 3.90V, etc.
And of course the black ones which can only be set every .10V, 3.80V, 3.90V, 4.00V, etc.
And the black ones, on full discharge over-heat and turn the screen black. They will work ok in balance mode though.
Since I had three extra blk. ones, I tried a few "dirt floor" mod.s
First, I tried a "splitter" balance lead that would allow 2 BM's on one bank of cells. Although it would discharge twice as fast, it wouldn't balance, as the single cells would "bonce" back and forth between the two BM's.
Then I tried attaching a sm. 24V, 40mm X 40mm computer fan on the back of the BM and running it off the 6S brick's Voltage. It wouldn't run on 22.4 Volts. Then I tried a 12V mini-fan and it works, discharging faster without the screen going black. Needless to say, it really hums on 22.4 Volts and the little motor is on the brink of burning up(I can smell it). I did two that way and use them when I need a fast discharge.
Looks like the new Turnigy discharger/balancer are the ones to use.
I would like a more detailed report if someone feels like it.
Things like what increments of setting? Every .01V, .05V or .10V?

Well, these last two posts jive well with my experience with my new 20 Ah of Multistar(4} of 6S/10 Ah).
There were no dud cells :lol:
The initial discharges/charges produced some unruly cells. Successive partial cycles with balancing every time has brought them together and it looks like they will be like my Turnigy 20C bricks in day to day use, that is, rarely needing any serious balancing.
Powering my mild mini-motor w/ a 17 A controller, there is virtually no Voltage sag w/ a fresh pack.
I only use Voltmeters to monitor my packs and use the crude calculation of 1 AH = 2 miles and now, w/ a 20 Ah pack I have a 40 mile range! Plus another 10 Ah pack that runs my frt. motor.
No more range anixity!

And I already have a LVC of 42V with both of my controllers, which in the past has proven the best LVC for 12S.
Really liking my new multistar Lipo :lol:

My new batteries are doing great, now nicely bedded in so they charge up nicely balanced now.

However my charger keeps going over-voltage while charging....
Not sure if this is only an issue on the 4s which was not an issue on 6s or the charger is stuffed and is quite possibly a cause of my 6s batteries aging prematurely

Basically when my Battery Medic says it is @ ~4.2v/cell (~16.8v total) the charger is reading closer to ~16.48v so it keeps on going... some cells showing 4.23 before I stopped it, they quickly come back down to about 4.17
my 'trusted' SkyRC 80w charger confirms that he BM voltage is accurate, not the Turnigy Mega 1000w charger.

So I am on the lookout for a new charging method, in the meantime, I set a timer and watch as the cells approach 4.2v and finish on my SkyRC charger.

How bad is it really to go to 4.23v per cell charging voltage? (I know fast charge on mobiles go to 9v but only in the first 80%)

Check the menues and handbook to see if there is a max charge voltage setting adjustment....there usually is.
But, 4.23v is not a big deal for charge cut off, just dont hold them at that voltage for long periods.

menvert said:

So I am on the lookout for a new charging method, in the meantime, I set a timer and watch as the cells approach 4.2v and finish on my SkyRC charger.

How bad is it really to go to 4.23v per cell charging voltage? (I know fast charge on mobiles go to 9v but only in the first 80%)

Click to expand...

If there is no calibration option on the charger, then just try to charge in LiIo setting, it stops on 4.1V/cell (which will be more in your case)

parabellum said:

menvert said:

So I am on the lookout for a new charging method, in the meantime, I set a timer and watch as the cells approach 4.2v and finish on my SkyRC charger.

How bad is it really to go to 4.23v per cell charging voltage? (I know fast charge on mobiles go to 9v but only in the first 80%)

Click to expand...

Hillhater said:

Check the menues and handbook to see if there is a max charge voltage setting adjustment....there usually is.
But, 4.23v is not a big deal for charge cut off, just dont hold them at that voltage for long periods.

Click to expand...

If there is no calibration option on the charger, then just try to charge in LiIo setting, it stops on 4.1V/cell (which will be more in your case)

Click to expand...

No calibration on this charger that I know how to access...Good call, I didn't even think of trying LiIo option with it's 4s taget voltage of 16.40v instead of 16.80, Which is ideal in this situation, also I can adjust the LiLo cell target anywhere between 4.08 and 4.20 (Lipo is 4.18 - 4.30) which will mean I can get a sweet spot for sure and have more control for a 95% charge scenario, Thanks

menvert said:

No calibration on this charger that I know how to access...
.......also I can adjust the LiLo cell target anywhere between 4.08 and 4.20 (Lipo is 4.18 - 4.30) .....

Click to expand...

.??? Contradictory comments ??

Hillhater said:

menvert said:

No calibration on this charger that I know how to access...
.......also I can adjust the LiLo cell target anywhere between 4.08 and 4.20 (Lipo is 4.18 - 4.30) .....

Click to expand...

.??? Contradictory comments ??

Click to expand...

I suppose, calibration is, when you can enter in special calibration menu and correct chargers readout values of balance and main leads to known real cell values (with aid of given battery and good calibrated multimeter). ICarger 3010b and few mid to high end chargers have it.
He only can adjust charge Voltage for given cells in menu but it will not correspond to real value.

Yeah, What parabellum said, adjusting the target voltage isn't the same as calibration.
I was watching it closely yesterday and initially voltage read is correct but as it ramps up amps to the full 38A, it only has to go to about 3A before the voltage drops rapidly, by as much as .3v (for example dropping from 16.67 to 16.42)
The input is about 11.4v from my 700w server power supply when at full load, so this may be too low for the step-up circuit to work effectively, alas I don't think the PS has any adjustable pots to get it closer to the ideal 12v

setting to 4.15v per cell seems to hit the right target, but ends under charged, which I can finish with my little charger, and know it's relatively safe in both counts.