Help! battery needs repair

minexplorer

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No not all chargers have adjustable pots inside , my Sans chargers and another similar one has the pot but a couple of others I have don't.
My Meanwell HLG has external pots for current and voltage adjustment, and are very good.
hi nealh could you give me specific models of adjustable chargers like that HLG u mention so i can look for sellers. for a 52v battery as u know. something that can allow tuning a 57v cut off for example instead of 48.8v. thanks
 

Nealh

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Mex a typo, I think you meant 58.8 not 48.8v.

For 14s you need at least I would say a Meanwell HLG - 120h - 54A, the A is important as this designates the model as having current & voltage adjustment. For this model it is max 2.5a in put current and all A models have +/- 10% voltage adjustment above and below 54v. The 54B has no voltage adjustment so imperative you buy the 54A identifier to the model. The only thing you will need to do is change the charge connector.
There are other ranges HLG -60, HLG -80, HLG -100, HLG -150 etc going at least up to HLG - 320 & HLG -600 it all depends on the current you want and input wattage for charging which is in the spec sheets on the Meanwell site or the vendors site.

These little beauties barely get luke warm because the ali shell acts as the heat sink.


 
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minexplorer

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Mex a typo, I think you meant 58.8 not 48.8v.

For 14s you need at least I would say a Meanwell HLG - 120h - 54A, the A is important as this designates the model as having current & voltage adjustment. For this model it is max 2.5a in put current and all A models have +/- 10% voltage adjustment above and below 54v. The 54B has no voltage adjustment so imperative you buy the 54A identifier to the model. The only thing you will need to do is change the charge connector.
There are other ranges HLG -60, HLG -80, HLG -100, HLG -150 etc going at least up to HLG - 320 & HLG -600 it all depends on the current you want and input wattage for charging which is in the spec sheets on the Meanwell site or the vendors site.

These little beauties barely get luke warm because the ali shell acts as the heat sink.


thanks so much nealh.yes a typo. im thinking if the cell banks can all even out around 41.0v then all is not lost.
one thing bothering me tho,has been a few cut outs requiring the bms plug pulled out and re inserted to get the bike going again.This was when even the lowest cell groups should have not been hitting the LVC of 42v. Once going downhill at just a cpl amps going over bumps.then worked fine at 20+amps uphill. Another time cut out after half a minute in pas2, even tho reading say 53v on the screen at rest before i pushed off. later kept in pas1 and bottom gear going up a long steepish hill,dipping to 47v but performed excellently. A few days back i went 8 miles with no issues freely using the pas 3 (20+amps)and throttle( 30amps). I just feel i cant trust the bike anymore.once the display is down to 50v under load im expecting a cut out any minute at anything over pas 1. i used to be able to give it brief blasts of WOT right down to 40v on the display without cut out.
im wondering if a loose bms plug could be a seperate issue. I am an idiot ,i have ADHD and can miss very obvious things.last year when this all started and i was using my multimeter to get cell voltage readings.i completely missed seeing i could read them from the back of the plug.i kept jamming the tester into the plug holes.now some of the bms pins dont probably grip as tight, as the plug doesnt fit tight anymore.(its not come out even slightly ,when ive had a cut out tho). Any thoughts cheers
 
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KirstinS

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thanks so much nealh.yes a typo. im thinking if the cell banks can all even out around 41.0v then all is not lost.
one thing bothering me tho,has been a few cut outs requiring the bms plug pulled out and re inserted to get the bike going again.This was when even the lowest cell groups should have not been hitting the LVC of 42v. Once going downhill at just a cpl amps going over bumps.then worked fine at 20+amps uphill. Another time cut out after half a minute in pas2, even tho reading say 53v on the screen at rest before i pushed off. later kept in pas1 and bottom gear going up a long steepish hill,dipping to 47v but performed excellently. A few days back i went 8 miles with no issues freely using the pas 3 (20+amps)and throttle( 30amps). I just feel i cant trust the bike anymore.once the display is down to 50v under load im expecting a cut out any minute at anything over pas 1. i used to be able to give it brief blasts of WOT right down to 40v on the display without cut out.
im wondering if a loose bms plug could be a seperate issue. I am an idiot ,i have ADHD and can miss very obvious things.last year when this all started and i was using my multimeter to get cell voltage readings.i completely missed seeing i could read them from the back of the plug.i kept jamming the tester into the plug holes.now some of the bms pins dont probably grip as tight, as the plug doesnt fit tight anymore.(its not come out even slightly ,when ive had a cut out tho). Any thoughts cheers
Random cutouts are the worst as they can be a bugger to diagnose. With a bbsxx the easiest way is beg or borrow (If you can) a battery, then a controller, then a harness, then an lcd. By swapping out each in order you can easily pinpoint the issue.

I had a VERY odd issue with my bbs02b. Thought my batteries were knackered, then the controller then the harness. In fact the LCD was faulty and showed massive voltage sag, randomly cut out the bike and other Issue. Soon as replaced it has been faultless. Batteries are not actually sagging at all! This is a very unusual case I'd suggest

A BMS swap wouldn't be too hard or expensive
 

KirstinS

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If you were a regular on ES then you will find that the 30Q is a poor choice of cell to use and cycle life isn't very good, 30Q suffers from self discharge after only about 50 cycles. Currently there is a very good thread going on over the other side of the pond and a couple of members are doing cycle testing up to 700 full cycles to see which of the popular best cells are better. LG MJI and M36 are showing to be top of the class, Panasonic /Sanyo bottom of the class. The Samsung 29E is also proving to be a top cell.
You try telling that to Jimmy! I got a good natured ribbing for choosing the mj1 over the 30q!
 

Nealh

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Kirstin have a look at the ES thread for cell ageing the 30Q is poor compared the LG 3500's, the MJ1 is a top 10a cell much better then the GA.
Sam 50E showing good results retaning 96% capacity after 250 cycles and matching the LG MJ1 & M36.

For price and performance alone a lot of the ES guys are still recommending and preferring the 29E, albeit in larger P groups.
 
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Nealh

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im wondering if a loose bms plug could be a seperate issue. I am an idiot ,i have ADHD and can miss very obvious things.last year when this all started and i was using my multimeter to get cell voltage readings.i completely missed seeing i could read them from the back of the plug.i kept jamming the tester into the plug holes.now some of the bms pins dont probably grip as tight, as the plug doesnt fit tight anymore.(its not come out even slightly ,when ive had a cut out tho). Any thoughts cheers
Likely I would say that jamming the probes in to the female sense connector may well have opened them up a bit and bad contact is being made with the male pins ( I use a pair of pins to push in and touch with my probes), more evident when current is asked or a jolt/bump may give a false reading causing the BMS to shut down.
The BMS my well be ok and you might be best to replace the 10s jst connector and splice and shrink a new one to the sense wires.
 
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minexplorer

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Random cutouts are the worst as they can be a bugger to diagnose. With a bbsxx the easiest way is beg or borrow (If you can) a battery, then a controller, then a harness, then an lcd. By swapping out each in order you can easily pinpoint the issue
hi kristen.i have no one to try this, but i do have an identical display the latest version 850c. i ll try it but i think the voltage sag is more likely the battery deterioration. some cell groups are unable to charge beyond approx 40.08v while others can reach 42v. Perhaps they sag worse as well as having less capacity. battery only 1500+ miles,maybe 70 cycles. im inclined to think the cut outs are due to loosened pins that nealh suggests may be affected occasionally by a high Amp demand.
 
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minexplorer

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For 14s you need at least I would say a Meanwell HLG - 120h - 54A, the A is important as this designates the model as having current & voltage adjustment. For this model it is max 2.5a in put current and all A models have +/- 10% voltage adjustment above and below 54v.


hi nealh. So if i buy say the 2.8a model i assume it will charge slower than the 5a charger the battery came with.thats fine. How do u set it up tho, to ensure each cell group only reaches a say max of 4.08v or 4.10v. do you have to multiply this by x14 and then set the HLG to that 57v odd, or do you set it to the 4.10v whatever. im a little confused as its not a bike charger,does it charge the seperate cell groups until they have all have reached the designated voltage u set then?thanks
 

Nealh

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It like a normal common charger it carries out constant voltage and constant current charging, similar to a generic charger it doesn't carry out any balancing that is left to the BMS. You set the max voltage you want your battery to reach 57.4v for 4.1v, once it detects the voltage level it will stop. If the cells when discharged are pretty much balanced then they should in theory remain balanced if the cells are all good, the issue we know is that 30Q isn't a great cell and that self discharge and poor cycle ageing isn't the best. This isn't just a recent thing and has been known for quite a while.
In your case you have good cell groups and bad cells groups so no matter what charger you use they are never going to be balanced whether you use 4.1v or 4.2v per cell group as you have one group that refuses to go above 40.8, that cell group is poor and will have a higher IR then the others sag is indicative of this.
 

minexplorer

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In your case you have good cell groups and bad cells groups so no matter what charger you use they are never going to be balanced whether you use 4.1v or 4.2v per cell group as you have one group that refuses to go above 40.8, that cell group is poor and will have a higher IR then the others sag is indicative of this.
thanks for that explanation nealh. regarding your second sentence, is it worth getting one of these chargers after all then and trying to get all cell groups to 4.1v? would it make any difference compared to the charger i have taking some to 4.20v whilst others may be 4.05 or 4.08 etc. my finger is poised over buy.
it may be after a cpl of charges they can all reach 4.1v. i had a group that wouldnt go above 4.08 first time i charged manually,but then went over 4.2v the second time. the battery has been sitting around a long time half charged. those low cells may come up to 4.10 with a few charges. rain preventing me cracking on with testing fully yet.
 
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Nealh

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The reason I bought one was because I can alter the current charge as well as the voltage easier, the ali shell is one large heatsink so my one barely gets luke warm.
 

minexplorer

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The reason I bought one was because I can alter the current charge as well as the voltage easier, the ali shell is one large heatsink so my one barely gets luke warm.
hi nealh ,i get that. My question tho is Earlier you discussed that it would be better if all the cell groups were charged to what the lowest could hold .Rather than higgledy piggledy final voltages. But It sounded as if you were then saying it wont make any improvement to performance. So im now confused again and dont know whether its worth paying out for one.
i noticed last year when u told me of the manual method of balancing cell groups i did that.then i put the battery on a full balance charge and it settled them all at 4.1v. for the first time the battery lasted all the way down to the 42v LVC and even dipping below, even with bursts of WOT.
 
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Nealh

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i noticed last year when u told me of the manual method of balancing cell groups i did that.then i put the battery on a full balance charge and it settled them all at 4.1v. for the first time the battery lasted all the way down to the 42v LVC and even dipping below, even with bursts of WOT.
How long did the 4.1v balance maintain it self after wards without further intervention ?

A lower charge current will be better for cell life and should be for balance (when not making use of the BMS balance feature) as it is a lower current being introduced so less of a rush for voltage to quickly rise.
Any low charging voltage is fraught with cell balance possibly becoming unbalanced, more so with cells that are already different in charge level voltages.
 

Nealh

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Going back to #19 can you show a pic of the chargers internal pcb.
 

minexplorer

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How long did the 4.1v balance maintain it self after wards without further intervention ?

A lower charge current will be better for cell life and should be for balance (when not making use of the BMS balance feature) as it is a lower current being introduced so less of a rush for voltage to quickly rise.
Any low charging voltage is fraught with cell balance possibly becoming unbalanced, more so with cells that are already different in charge level voltages.
Hi nealh,It eventually went out again. could be some cell groups lost a little charge over days sitting around causing imbalance to return.i notice the display shows the voltage is holding tho. So u think the lower 2.5Amp charge current (mines 5Amp)combined with setting to only reach 4.05-4.10 should do a good job of keeping them even ,if i understand right? three square blue components with adjustable screws.2 marked W 102 122 T ,1 marked W 502 121 T ??
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