local help near uxbridge london

[cware05]

Hi I have posted a few times and have now built and destroyed about 6 bikes but have reached the limit of my technical expertise regarding battery technology and am asking for someone to not only be capable of helping me understand advice but also willing to physically show me or help me make up a couple of packs in lithium cobalt ? (repair one and modify another)and make some lifepo4 packs.

not sure if this goes on much in the London area but I thought I would give it a go.

I have tons of ideas but need to be shot down in flames if they are stupid and also pointed in the right direction on bms's/alarms/chargers etc. to purchase
I bought 2 x Chinese tlh 48v n18650 packs in 10a (n18650 s06l l22r1 16507 on the cell)which have a bms built in but they have not been of any standard at all I would probably rate them at about 3 amp connecting strips internally and would like to repair one pack which has 5 dirty corroded/leaky cells out of the 65 fitted in the pack,
after about 5 months use which has now gone short circuit and refuses to charge (this is where my technical ability goes all fuzzy) I don't know if the bms has got the hump or the broken terminal shorting in the pack has done damage or simply leaky cells is the problem but when I resoldered the break I still only have 0.01 v in the pack instead of 54.6v.

the other idea I have is the lifepo4 cells which can be harvested from the 9 packs I purchased as new but uncharged for about 2 years and making up some packs from those as I intend to make an electric motorcycle as well at some point these cells are allegedly 3.7v 10a but I have no way of verifying this (phylion battery 2ga24559ba24558b cells xh259-103 pack) there are approx. about between 7-11 (24v and 36v) in each alloy enclosure,although I have only looked at one of the 24v(25.9) ones so far. (I have put on the numbers on the cells in case they prove useful to the clever people out there ) these will need individual cell charging as they have hardly any voltage and no where near enough for the charger to recognise them but what do I charge the cells with at what voltage ?
also is there available all different voltage bms ?
I would want a 48v 20a bms and charger and a 72v bms and charger and for the motorcycle possibly an 84v/96v bms and charger preferably with alarms for discharge as I will be pushing as hard as they can go with an 11k motor hopefully .

the reason for my change in direction is that my controller stopped on my overvolted bike and when I replaced the controller with a higher amperage very basic eBay one 2 input wires 2 output wires , it seems to be sucking the life out of my functioning 48v 10a/max 25a pack, it has massive torque once rolling about 3x more than experienced with the previous controller but then cuts cleanly and does nothing until the battery terminal is separated and reconnected and off it goes again it was listed as 24-60v and up to 1000 w so sounded ideal but I think I must be drawing more than the battery is willing to give I did try it on a 48 volt 7a lead acid pack that has dubious life in it and it went but blew the 10a fuse and the holder got really hot when I increased the amperage to a 30a replacement

it is a cheap and nasty 180w 24v brushed motor in a 26" rear wheel and needs to be @ about 9-10 mph before using power as it judders and complains below this and it pulls straight up to about 22 mph before cutting but it really loves the high revs at top speed.

not sure if anyone thinks they can help in person or online but I have kind of given up through my lack of understanding how to proceed in reviving and completing the pack build safely .

cheers in anticipation
Darren

 

[dnmun]

just too much to follow.

you have 9 battery packs which are two years old and have never been charged so the cells are all dead?

you wish to make an 84V battery with them and use that to drive a 250W brushed motor?

 

[cware05]

Thanks for the quick response and not quite what I meant.

I am seriously rubbish at this communication thing online and ask too much, ramble about stuff and often don't really understand replies until someone shortens it down and explains some of the big words but I am enthusiastic !!

I need to make one functional 20a 48v pack for the 24v 180w motor from 2 x 48v 10 amp packs but one pack has 5 cells duff ?

and I want to make a 72v 20/30a pack from the 9 packs if they are revive able.(60 cells if I can save that many for the 30a less if not so many live) and that would supply 74v I think.



cheers
Darren

 

[dnmun]

i doubt if any of the cells that drained to 0V will ever work.

you need to provide a picture of the insides of the battery so we can see how it is constructed and you need to measure the voltage on each cell and list them.

 

[cware05]

so initially if I just put a multimeter on the individual cell terminals with a 6v 2a supply and charge till 4.3v if that happens would this be a reasonable way to revive the cells ?

and put the pack back together to charge with the bms once the pack goes past the 25.0v mark to balance them ?

then reconfigure the packs to 74v purchase and fit the possibly mythical bms and purchase a 72v charger and charge and balance again in the final format ?
or am I way off ?
cheers

 

[dnmun]

repeat. you need to open the pack and show pictures of what you have. you need to measure the cell voltages and list them. do not charge the cells up before you do this.

 

[cware05]

sorry crossover of posts I will get the packs out of the garage in the morning and get some pics of configuration and voltages for your consumption and advice.
cheers

 

[cware05]

ok stripped a fresh 0.0v pack from the pile back to 10 rectangle cells split into 2 x 5 cell packs linked positive negative with metal strips onto riveted copper and aluminium terminals and an alloy bms with 11 coloured wires on a plastic plug and 3 larger wires exiting from the body of the bms.

I am attempting to get the photos uploaded but not able to get them off my phone and manipulate them for some reason so that will need some work.

the individual cells readings are as follows
1,bottom set of cells with a fat yellow link wire from + to negative and lilac/purple bms wire on negative 0.00v
2,metal link strip 1.8v
3,white and grey bms wire 0.00v
4,metal link strip 1.0v
5,brown and black bms wires and fat blue bms wire to negative terminal

upper pack of 5
6,black, brown, red bms and fat red to fuse 1.1v
7,metal link 0.00v
8,orange and yellow bms 0.00v
9,metal link 1.00v
10,green bms and fat yellow to bms 0.00v

obviously this will make much more sense when you can see the pictures of the wires and cells and I will try to get them up asap

if I read from cell 4 negative terminal to cell 6 positive I get 5.00v which has confused me as nothing is reaching the output terminals on the base of the main pack.
cheers

 

[dnmun]

you can use a digital camera and then download the pictures to your laptop and then use the download attachment section below the posting dialog box. when you download it asks for the file, so you use the browse to find the picture in your picture albums, click open to open the file in the upload attachment box, then 'add file'.

sounds like you have some 10S packs with a BMS.

 

[cware05]

the other style of pack 48v 10a consists of 65 x 18650 cells welded into small packs of 5 and then linked via a single circuit board bms with a thin sheet ally heat sink and welded into midi packs of 15 cells which are insulated by red card and formed into a bar about the width of my forearm(which you cant see I know sorry) the majority of the cells are between 2.4v and 3.9v apart from the 5 rusty possibly leaky cells which seem a uniform 0.02-0.04v so I am assuming the dead cells have stopped the pack from functioning, but this still leaves the fact that the charger cuts instantly when connected.

do you need every cell reading on all 65 itemised ?
I am digging out the old camera now thanks for that

cheers

 

[dnmun]

you want to go through all of the cells and list the voltages, and write the voltage of that cell, which is a group of 5 cylindricals from what you said, on the cell so you have a record to use to work from.

yes, the dead cell at 0V has to be cut out and removed. no need to even measure them. if the rest are at 1.8V or above then the pack should be functional later. just a 15S pack.

i can show you how to hack the BMS to allow it to charge and discharge then when we can see how it is wired up. or you can buy a 15S lifepo4 BMS.

 

[cware05]

ok changed pc back onto an old vista laptop as the only way to get these pictures on looks like its windows 8 that dosent like me not the phone
hope there is enough clarity i am taking some pics of the other type cell now
cheers

 

[dnmun]

we should start holding contests for deadest of dead batteries. so if you cut out just the ones that are zero, how many are left? if anything below .5V then how many? and the 48V pack is the one with the leaking cells. looks like you had some leakers in those pictures too.

 

[cware05]

thanks for the clarification looks like i have plenty of testing and listing to do !
is it best then to remove all the dead cells from all the packs and collect the live ones together and see how many i can get ?
is there nothing i can do to try to revive the big cells once they have reached "0.00v"?

the small cylindrical cells i have attached to this post came in two 48v packs one of which still functions is there a reasonably easy way to use the good cells from the dead pack added to the good pack and make one higher amperage 48v or better still my 72v 10a pack if that is enough to run my mid mount gng 48v 450w motor off road ?

I already have a 30a 72v controller from gng so it should be quite happy I think and after reading about peoples experience on here I am carrying out the tensioner mods for a reasonably trouble free ride, not like my luck with batteries lol.



still not sure how the bms works or how they managed to use 65 x 3.7v cells to obtain 48v are they really low amperage ?
cheers

 

[dnmun]

what is the chemistry of the blue cells? is it lipo or limn2o4? what does the BMS look like? those are 9 of the 18650 cylinders/channel? which is the dead one? top or bottom?

 

[cware05]

Hi the chemistry is a bit uncertain as the guy only spoke and wrote Chinese and I don't, even with the translation on the pc it was interesting buying them.
limn2o4 sounds similar but I am sure there was a C in the middle of it somewhere.

he said it was the latest best type and much better than lipo for weight, shame they didn't last.

the dead leaky cells are 5 in one small pack at the bottom(part of a collection of 15 in total but the others are all 3.9 v ), when I stripped off the heat shrink and card protection there was a snapped metal strip which had been making and breaking and I assume overheating the small pack, hence the leak and loss of volts.

the bms is a single circuit board at the very top with a mass of red wires on a single plug and 3 slightly fatter wires come off the board at the top

 

[cware05]

stripped another 2 packs today and I only got another 3 live cells so my expectations may have been a bit high at this ratio of good cells per pack I will be lucky to hit 48v 20a.

but at the price I paid it's not a problem so long as the packs can be remanufactured reliably, and I get some use out of them.

 

[cware05]

wow long time no talk.
family and work have taken total control of my life till today so I hit the batts this morning stripped 9 units down in total from their ally cases and tested voltages.
all the cells look to be identical 10a steel rectangles in 10 x 4.2v cell (42v) 36v, and 7 x 4.2v cells (29.4v) 24v configuration spot welded together and a square bms on the top in the aluminium tube with plastic end caps .
I tested without charging as suggested and the majority (40 cells) have between 1.2v and 4.1v with 20 being 3.8v or above
with 5x sub 1.0v cells the lowest being .7v.

not really sure where I go next with my evil master plan, but think I would like to go 72v 20a if possible ?
would I have to make 4x 36v 10a packs and link them in series parallel to get this or is there a bms off the shelf that would manage 1 big 72v 20a pack ?
ideally I would also like just 1 x 72v charger to simplify the process if possible ?

I have a gng 72v 20a controller that may need beefing up on the shunt (I shall have to look into this as I have only ever read about this on here )

this would be to power my gng mid mount 450w 48v kit with the battery in the middle of the triangle of my Ideal full suspension mtb with a fibreglass box and run it as an electric moped, a pretty heavy one as well lol.

I am going to start separating the cells and grouping the live ones ready to re-assemble into the new configuration to fit the frame next week.
should I charge these good ones individually to 4.2v and discharge to see how they behave next ?

Is there any revival process for the 20 x cells showing .3v or less (most are .1v or 0v ) It seems such a shame as these cells have gradually trickled away and have never been discharged through a motor ,or are they simply expensive doorstops now ?
cheers
Darren

 

[dnmun]

don't use them for doorstops because if they leak they will ruin the floor.

if you can post up picture here on your thread it helps to figure out what you are talking about. please don't just link files, post the picture itself.

 

[cware05]

Ok I have just downloaded shrink pic and hope it lets me send some pic's for you the ones off my phone are huge and windows is really being funny with me every time I try to re-size anything.
didn't work again only one shrunk down enough to send, I will have another go in the morning
kind regards
darren

 

[cware05]

after looking up the 259-10j phylion battery from the sticker on one pack they seem to be fairly badly thought of lithium ion cells but might do me for a year on my bike if I am lucky, and you can give me pointers on how to arrange the cells and bms correctly.
kind regards
Darren

 

[cware05]

Model
XH259-10J(7IMP18/66/133(10)-005)

D×W×H
245×147×85mm

Normal Voltage
25.9V

Nominal Capacity
10Ah

Weight
<3.35Kg

Internal Resistance
≤75mΩ

Discharge Voltage Limit
2.7V(any cell)

Protected charge Voltage
4.25V(any cell)

Charge Voltage Limit
29.4V

Max Charge Current
2A

Max Discharge Current
19A

Nominal Discharge Current
10A

Charge Method
CC/CV(matched charger)

Capacity@1c rate
≥10Ah

Cycle life
500times（cycle@RT,1C rate,100%DOD）
this is a more modern plastic boxed version but the cells seem to be the same inside ?