ADVICE/ADVICE - Think my battery has Finally died !!!

[bilabonic]

1. RED - BLACK -3.75V
2. RED - YELLOW -7.5V (3.7V)
3. RED - GREEN -11.25V (3.75V)
4. RED - WHITE -14.99V (3.74V)
5. RED - BLUE -18.74V (3.75V)
6. RED - BROWN -22.48V (3.74V)
7. RED - RED -26.23V (3.75V)
8. RED - BLACK -29.98V (3.75V)
9. RED - YELLOW -33.7V (3.72V)
10.RED - GREEN -37.5V (3.8V)
11.RED - WHITE -41.2V (3.7V)
12.RED - BLUE -44.9V (3.7V)
13.RED - BROWN -48.7V (3.8V)

If i had this problem in work i would just order several batteries mate...lol

 

[Nealh]

Group readings are all good though a little unbalanced.

Plug the bms jst back in to see if it will switch on and allow charging, sometimes this can work.

We know from your reading that discharge also shows 48.7v which matches the cell readings, so most likely fault is with the bms as the jst readings show each sense wire is contacting and connected.

Apart from checking and looking to see that there are no bad bms board connections/solder joints, a new bms might be in order.

 

[bilabonic]

Same as before 54.7v in/48.7v out.

Charger LED constant GREEN even when unplugged (it only has one LED view hole BUT surely there is a RED led which should be on when disconnected/not fully charged ??

The battery has charged overnight with a constant green LED....

I also remember my old 36v battery would show 42/43v when fully charged..

 

[Nealh]

The charger led is the same led it changes colour green /red/green depending on whether current is flowing or not.
Green when only charger switched on at the mains is no current passing but ready.
Green when charger & battery are connected is charging finished no current applied, at this point the bms may be balancing at a very low rate or has switched off not allowing further current flow.
Red is simply current applied and charging.

In operation they are as simple as that.

 

[Nealh]

When I fault find a battery after the bms check I strip the battery pack bare and remove all heat shrinking etc and check all the cell ends.
I look for discoloured busbar tabs on both parallel and series connection to see if there is a weak link, also using a thin wooden pointed dowel I try and see if any welded tab is loose adding a little pressure upward levering pressure. I also check sense wire solders just for the sake of it but as you are getting good cell reading from jst they would appear to be fine.

You can't test a bms it will either switch on or off and are to intricate to fault find unless you are a genius in mini electronics circuitry. Often if a cell group is very low then you can assume a bleed resistor has failed. Only other option is to borrow 48v charger from a nearby ebiker ( phone a friend) and see if their charger works or not, if not then replace the bms.

Lastly try a wire continuity checks of the V+ from battery to charge port and C- from bms to charge port. Also the bms to B- to battery B-.
BMS P- is to discharge port this is good as you see the pack voltage as discharge reading.
Also BMS B+ to battery B+.

 

[Nealh]

Although the pic isn't very sharp enlarged, looking at pic BMS1 in #31 bottom right is the CH charge V-. In appearance it looks as if the solder joint is slightly blackened at the wiring and also the Mosfet up and right marked rfr3607 looks to have a damaged /holed casing on the lhs, though this may be something on the surface and optical with an enlarged pic view.

 

[bilabonic]

The charger led is the same led it changes colour green /red/green depending on whether current is flowing or not.
Green when only charger switched on at the mains is no current passing but ready.
Green when charger & battery are connected is charging finished no current applied, at this point the bms may be balancing at a very low rate or has switched off not allowing further current flow.
Red is simply current applied and charging.

In operation they are as simple as that.

Yes i know that, BUT i was just trying to state that this charger has only one led viewing area, i have other charges with 2 leds.
It could be a dual green/led or there could be both on the PCB...

 

[bilabonic]

Well, i just tried the battery on the bike, showed zero bar on the LCD although that is nothing to go by...

It went about 30 meters and died...After 10secs it would give me another 'short burst'....

I did check the continuity as above and all is OK.

I did notice the battery was VERY warm opposite end of the BMS...

I highly doubt the the brand new charger is U/S...

I suspect the BMS....I may check all battery connections later, the pic gets reduced in format on here when uploaded but i did not see any burning etc on the PCB...

It now measures 48.1v after that 'little run'

Cheers

 

[wheeliepete]

It would seem there is also a discharge fault with the BMS, as the bike should run OK with that voltage, esp. as the cells are quite well balanced.

 

[wheeliepete]

If you want a recommend for a new BMS, I've used ANNPower on Aliexpress a few times, but stuff can take a couple of weeks to arrive.

https://www.aliexpress.com/store/product/3-7V-cell-13S-48V-40A-lithium-battery-BMS-With-ON-OFF-switch-and-balance-function/623665_32847121949.html?spm=2114.12010612.8148356.9.bbce7abevge2i1
This one will do the job, slightly different to wire up, just check dimensions will fit your case.

 

[bilabonic]

None of it is making sense to me BUTultimately this problem arose when i plugged in the old charger and there was a large draw of current...

It blew the old charger, it had NO output.

Has it blown the BMS as well ??

What i find strange as well is that the LCD on the bike shows a flat battery (i know these are NOT reliable in any way, but it always showed 3 bars after a few mins).

Also there is a small push button/PCB/led assembly on the battery itself and when pressed it shows FULL bar/Green

Where would i source a new BMS for this ??

 

[bilabonic]

If you want a recommend for a new BMS, I've used ANNPower on Aliexpress a few times, but stuff can take a couple of weeks to arrive.

https://www.aliexpress.com/store/product/3-7V-cell-13S-48V-40A-lithium-battery-BMS-With-ON-OFF-switch-and-balance-function/623665_32847121949.html?spm=2114.12010612.8148356.9.bbce7abevge2i1
This one will do the job, slightly different to wire up, just check dimensions will fit your case.

I need bike up/running ASAP mate as i do not drive and it's been a total nightmare atm !!!

Thanks

 

[bilabonic]

I'm considering just getting a new battery and soldering the old socket wire onto it (it will still be removable).

I need to up and running ASAP...Why are some people listing batteries MUCH cheaper but stating 500w (£195) even though the specs are same as 1000w ??

https://www.ebay.co.uk/itm/48V-12-5AH-500W-Black-TIGER-SHARK-Li-oin-Battery-for-Electric-Bicycles-E-Bike/123309868627?_trkparms=aid=555018&algo=PL.SIM&ao=1&asc=20140122125356&meid=0e139ac09def43b1baf6b5bb692fc03c&pid=100005&rk=5&rkt=12&sd=183304283649&itm=123309868627&_trksid=p2047675.c100005.m1851

The one abovehas the the exact same fitment (just two holes)....BUT surely i can just solder on cheaper/differing brand ??

Anyone recommend one ?

Cheers guys, getting frustrated now...lol

 

[bilabonic]

Sorry meant this, just this is listed at 1000w...lol

 

[wheeliepete]

I can't recommend a UK seller as I always source my parts from China, but there's a couple on Ebay that should do the job.

This one is only rated at 15 amps, but 45 amp protected, so should be OK if you are running the standard controller.

https://www.ebay.co.uk/itm/48V-54-6V-13S-15A-18650-Li-ion-Lipolymer-Battery-Charging-BMS-PCB-for-500W-ebike/123246841202?hash=item1cb2158d72:g:6fIAAOSw8CZa0SIA:rk:9:pf:0

Or this one, which is identical to the one I linked to from China, but over twice the price. Bloody rip off.

https://www.ebay.co.uk/itm/13S-48V-40A-BMS-Li-ion-Cell-Battery-ANN-Balanced-bike-E-bike-UK-seller-UK-stock/123463308851?hash=item1cbefc9633:g:6tIAAOSwkvtb2tGi:rk:19:pf:0

You will notice there is no + connection on these, so you will have to connect the large + wire from the battery direct to the discharge port.

 

[soundwave]

prices will differ because of the make of cells and there capacity but if you had a pack made buy bga you can pick the cells you want at a price you like.

 

[wheeliepete]

OK, if I needed a battery for a reasonable price quickly, I would buy this one. Shipped from Germany, but I received a battery from them in 3 days last month. Make sure it will fit your frame.

https://www.yosepower.com/en/product/Downtube-Big-Power-48V13Ah-HaiLong-Lithium-E-Bike-Battery-with-USB-Battery-Switch-E-bike-DIY-70.html

 

[bilabonic]

I can't recommend a UK seller as I always source my parts from China, but there's a couple on Ebay that should do the job.

This one is only rated at 15 amps, but 45 amp protected, so should be OK if you are running the standard controller.

https://www.ebay.co.uk/itm/48V-54-6V-13S-15A-18650-Li-ion-Lipolymer-Battery-Charging-BMS-PCB-for-500W-ebike/123246841202?hash=item1cb2158d72:g:6fIAAOSw8CZa0SIA:rk:9:pf:0

Or this one, which is identical to the one I linked to from China, but over twice the price. Bloody rip off.

https://www.ebay.co.uk/itm/13S-48V-40A-BMS-Li-ion-Cell-Battery-ANN-Balanced-bike-E-bike-UK-seller-UK-stock/123463308851?hash=item1cbefc9633:g:6tIAAOSwkvtb2tGi:rk:19:pf:0

You will notice there is no + connection on these, so you will have to connect the large + wire from the battery direct to the discharge port.

Yea i looked at them on Ebay, rip off !!! at 91mm on widest point it will not fit in the case anyway...

 

[wheeliepete]

Hold on a mo, you mentioned 500 watts, what motor are you running and what's the amp rating on the controller? You really don't want a battery with cheap Chinese cells in it if you are running over 20 amps.

 

[bilabonic]

OK, if I needed a battery for a reasonable price quickly, I would buy this one. Shipped from Germany, but I received a battery from them in 3 days last month. Make sure it will fit your frame.

https://www.yosepower.com/en/product/Downtube-Big-Power-48V13Ah-HaiLong-Lithium-E-Bike-Battery-with-USB-Battery-Switch-E-bike-DIY-70.html

Nope that will not fit, it's too long... this is the exact one i have fitted.

But unable to add to basket as i can not add location for the 48v ?

https://www.yosepower.com/en/product/Original-Down-Tube-36V16Ah-/48V11.6Ah-For-Hub-motor-Electric-Bicycle-Lithium-ion-Battery-Black-138.html

Note the slope of the battery/holder at the bottom of the down tube...

Lucky i checked..