battery upgrade Question for double battery build

[EnPagés]

9 hours ago, zlymex said:

Welcome here!

Both battery pack will do but you need to check the thickness of the pack from Alibaba which seem to me that the BMS is thicker than usual being with an aluminium heat-sink.

The high discharge rate pack is good, it will ease the loading of existing pack and make the whole thing more powerful together with the old pack. You may need a Y-connector if adding a second battery pack which can be purchased or DIY.

Parallel battery packs of mixing brand cannot be regarded as bad idea. I had two different types of packs in parallel for my T260(240Wh Chinese brand battery), Sanyo and Panasonic and they live together very well for more than a year.

Thank you very much for your soon response, I've started to negotiate with the seller. I think the BMS it's changed depending the power of the motor, hope it's well calculated because I can't find anywere the specs for the sony battery 260Wh of the Gotway.

Once again, thank you!

When I receive the new battery pack I will post it and explain how about the difference with the High Rate

[zlymex]

10 minutes ago, EnPagés said:

I can't find anywere the specs for the sony battery 260Wh of the Gotway.

If you mean Sony V3, HERE is one.

[Jug]

6 hours ago, Chriull said:

Seems that noone answered to your question till now - or did i miss a posting?

Definitely - if you introduce new connections by your soldering you change the way the BMS can/will work + you could shortcut cells (think you did not by now - you would have noticed immediately). Could be that you had good luck - the green stuff on the traces of the PCB is "solder resist" and isolates the traces (a bit..) However you should in any case repair all such things!

And you want to use less solder ( https://learn.adafruit.com/adafruit-guide-excellent-soldering/common-problems ) - the BMS in combination with the batteries is quite a safety critical part. I would try to build it up carfully and as perfect as possible...

Edit.: The overlap you show on the picture would be a shortcut of the battery cell(s) 16. Since the PCB traces are not molten you have no shortcut by now. But a minor scratch by vibrations etc could lead to one!

Repairing this situation could again lead to a shortcut of this cell. Too much heat or scratching could destroy the "solder resist" (green "layer" on the trace) and it would not isolate anymore. So you should do this very carefully! Maybe you could remove the battery cell 16 before this in some way?

Edit2: You could unsolder the connection at B16+ first and then repair the situation at B16-. Should be imho the safe(r) way to go...

PS.: At "B13+" you have a small ball of solder lying around. This could be held loosely by some soldering flux - you should remove this too, since it will loosen itself over time and then you have a conductive piece moving around your BMS...

Thank you for remarks, 

I did removed the batteries from that BMS, and i solder it on another BMS but this time i did really careful, so there is no overlapping now!  

[Maxime]

I suggest that if one or several batteries or linkages is faulty, you could try to mesure Volts DURING discharge, using some load like a not-too-powerful classical lamp. Perhaps some of you could tell which power to use, not to have too high amperas, but still near those when you run.

Or tell me if I am wrong...

[Jug]

@zlymex

I have uploaded video to youtube here is link: https://www.youtube.com/watch?v=7nKn7yJtIZA

and here is screenshot of gotway app 

I have charged it fully, as on the video you can see when i accelerate the power drop down immediately and i can not accelerate quickly like with original 130w batteries,

with original battery pack i never go to zero when accelerate when is fully charged, they have power, but with this custom there is no power but i got more mileage with this custom pack.

What is wrong here? 

This is 2 parallel and 16 series Samsung ICR18650-30B

[Maxime]

Sure you can use the complete battery load, but you cannot obtain the current neccessary for speeding. If it is good with old battery, it must not come from the wheel but from your new battery, inluding BMS. Try the test I suggested, you will get more info before posting again, we don't have enough elements for a more precise diagnosis.

[Jug]

5 minutes ago, Maxime said:

Sure you can use the complete battery load, but you cannot obtain the current neccessary for speeding. If it is good with old battery, it must not come from the wheel but from your new battery, inluding BMS. Try the test I suggested, you will get more info before posting again, we don't have enough elements for a more precise diagnosis.

Thanks 

Ok, i will try this, what kind of lamps i need? and do i conect lamps directly to battery or thru BMS? 

[Maxime]

As your wheel probably uses around 100 W when running on flat land, you can use a 100 W lamp or even more if you have a big motor.

Pay utmost attention to avoid shorts.

Connect after bms and see if the power stays stable or decreases as soon as ON as when rolling.

Then, you can perform same measure (OFF….. ON) for the Volts before bms.

- If it decreases same as first measure, the battery itself is ill. Keep the lamp ON and check V on each element or pair.

- If it does not decrease same, the bms is ill.

[zlymex]

20 hours ago, Jug said:

I have charged it fully, as on the video you can see when i accelerate the power drop down immediately and i can not accelerate quickly like with original 130w batteries,

I was thinking the same thing as @Maxime . Find a way to measure the voltage output of the BMS while running the EUC. Also, check the wiring connections to the BMS.

[Jug]

@zlymex @Maxime @Keith @esaj

So, here is the result, i tried what you proposed and i went to buy some car lights and i got 4x 55w, 12volt.

I connected them in line and when i tried to discharge the battery i got a big spark and all lams blow up! 

so i failed on this checkpoint... 

Next what i did is i attached battery to the euc but i left charging cable unattached (for measuring voltage) and on his stand (support) i start it and leaned forward to achieve  

maximum speed and i measured voltage on the charging cable, before cutoff the minimum voltage drop down was 61.5V from 67.5V, then i tried that also but with multimeter attached directly to battery bypassing BMS, the voltage drop was same.

Then i tried with original battery pack and there i had 64V. so there is some difference but all this was without load so i don't know is this give some result or no!

Yesterday i decided to attach the good one (original 130w) and the bad (builded one) in parallel to test how far i can ride with this packs!

I give up when my toes start to freezing with pain 

I rode +- 20km for 1h45 and when my toes decide to give up i ended with 40% battery on my gotway android app! 

So i think i could go for 5km more if i could finish it up.

here is the way pat where i was riding and screenshot of gotway app when i decide to give up!

[Maxime]

All I can say, and first is 4 lamps 12 V in line = 48 V ! So, not surprising they blew up with 67+. In my mind I was thinking to a 220 V lamp, but I should have said, sorry...

As for the bad battery, probably it can take a part of the W needed, rather small on normal riding, but could recharge the normal battery in low speed times, or slopes down ?...

When you tried the old one, does the voltage, after decreasing, climbs up again if you stop using it ? This is probable as you have gained plenty of energy when wheeling with both batteries. Does your App can show the total Wh used on a journey ?

[Jug]

10 hours ago, Maxime said:

All I can say, and first is 4 lamps 12 V in line = 48 V ! So, not surprising they blew up with 67+. In my mind I was thinking to a 220 V lamp, but I should have said, sorry...

As for the bad battery, probably it can take a part of the W needed, rather small on normal riding, but could recharge the normal battery in low speed times, or slopes down ?...

When you tried the old one, does the voltage, after decreasing, climbs up again if you stop using it ? This is probable as you have gained plenty of energy when wheeling with both batteries. Does your App can show the total Wh used on a journey ?

With bad battery when I go down hill they do recharge, if that was question. 

Original battery climb back again after decreasing, they work normally.

My app does not have Wh unfortunately! :-( 

But I got bigger autonomy with both packs! :-) 

[Maxime]

That was not the question, read again.

[zlymex]

15 hours ago, Jug said:

i measured voltage on the charging cable, before cutoff the minimum voltage drop down was 61.5V from 67.5V, then i tried that also but with multimeter attached directly to battery bypassing BMS, the voltage drop was same.

I suggest that you measure the individual cells to see which one(or all) drop down the most. Be careful not short circuit them.

[Maxime]

Thanks, Zlymex. I think, as I said long before, it is the only way to find the defect and not burn with the wheel. But apparently, Jug does not want...

[Jug]

On 1/19/2016 at 0:28 PM, Maxime said:

Jug does not want...

@Maxime why do you think i do not want? 

I did what you suggested didn't i, but the lamps blow up and therefore i could not measure individual cell. 

Problem is i did not know how 

Now when you said i need 220v, when i came home from work i went and buyed this lamp 240w

and here is the result;

The battery voltage was 66.6V when i connected lamp it drop down to 64.8V, same thing was without BMS (directly on battery)

Then i measured each cell and here is what i got:

With lamp attached, and that in quotes are without load "normal voltage" 

b16> 3.99 "4.16"  b15> 4.01 "4.18"

b13> 3.99 "4.16"   b14> 4.07 "4.21"

b12> 3.98 "4.16"   b11> 4.07 "4.19"

b19> 4.12 "4.21"   b010> 4.02 "4.19"

b08> 4.13 "4.19"   b07> 4.14 "4.19"

b05> 4.14 "4.19"   b06> 4.06 "4.21"

b04> 4.10 "4.20"   b03> 4.07 "4.20"

b01> 3.97 "4.16    b02> 4.11 "4.20"

 

I tried also with original battery and voltage drop from 66.9V to 66.3V when connected to lamp.

 

 

[Maxime]

OK you could do. But bad news, it seems that all your elements are poor quality, perhaps good for low consumption device, but not for a wheel. You can use it as you did, with both batteries together, it will probably not generate a problem. I hope the quality will not still go lower. But I suggest you use these figures to show your seller the poor and abnormal quality of his battery !

Good runs !

[zlymex]

I agree with @Maxime, those cells seems not suitable for EUCs.

For a 16s1p pack, max. constant discharge current of 15A type or better(current is higher) is suggested such as 
----Sony VTC3, VTC4, VTS5
----Samsung 20R, 25R and 30Q
----LG HE2 and HE3

For a 16s2p pack, max. constant discharge current of 10A type or better is suggested such as  
----Panasonic PD, PF and BD
----Sony V3 and VC1
----Samsung 22P
----LG MH1 and MJ1

For a 16s4p pack, it mostly used for EUCs of high power and better performance, the requirement should be the same as 16s2p.

Common 18650 cells mostly found in notebook computers are not good for EUCs such as
----Panasonic NCR18650A, NCR18650B, NCR18650BE, NCR18650G
----Samsung 22F, 26F, 26H, 28A, 29E, 30B, 32A
----most of other LG cells except mentioned above.

[Jug]

8 hours ago, zlymex said:

I agree with @Maxime, those cells seems not suitable for EUCs.

For a 16s1p pack, max. constant discharge current of 15A type or better(current is higher) is suggested such as 
----Sony VTC3, VTC4, VTS5
----Samsung 20R, 25R and 30Q
----LG HE2 and HE3

For a 16s2p pack, max. constant discharge current of 10A type or better is suggested such as  
----Panasonic PD, PF and BD
----Sony V3 and VC1
----Samsung 22P
----LG MH1 and MJ1

For a 16s4p pack, it mostly used for EUCs of high power and better performance, the requirement should be the same as 16s2p.

Common 18650 cells mostly found in notebook computers are not good for EUCs such as
----Panasonic NCR18650A, NCR18650B, NCR18650BE, NCR18650G
----Samsung 22F, 26F, 26H, 28A, 29E, 30B, 32A
----most of other LG cells except mentioned above.

@zlymex @Maxime, Thank you very much for your time, effort and help! 

I have some more question, is it safe if I use it like I was in parallel?

Or how is better performance, like I already attached in parallel or, if I attach charging cable to bad battery pack then from discharging cable of bad battery to charging cable of good battery pack, and from discharge cable of good battery to motor?

Which connection is better if I can use the bad battery pack safe?

Thanks :-) 

[zlymex]

24 minutes ago, Jug said:

@zlymex @Maxime, Thank you very much for your time, effort and help! 

I have some more question, is it safe if I use it like I was in parallel?

Or how is better performance, like I already attached in parallel or, if I attach charging cable to bad battery pack then from discharging cable of bad battery to charging cable of good battery pack, and from discharge cable of good battery to motor?

Which connection is better if I can use the bad battery pack safe?

Thanks :-) 

Parallel connnection is safe so long as all the batteries to be connected are safe and roughly they are the same voltage before connection.

Parallel connnection is better because charge and discharge current is shared among battery pack connect. Although it might not be shared evenly, it's better than single use alone. The less discharge and less charge current will make them safer. However, you need two Y shaped connectors(one for discharge, the other for charge) to make the parallel.

Although I said that some cells are not suitable for EUC use, these cells can be used in parallel with existing(and good) packs to increase mileage.

[Jug]

1 hour ago, zlymex said:

Parallel connnection is safe so long as all the batteries to be connected are safe and roughly they are the same voltage before connection.

Parallel connnection is better because charge and discharge current is shared among battery pack connect. Although it might not be shared evenly, it's better than single use alone. The less discharge and less charge current will make them safer. However, you need two Y shaped connectors(one for discharge, the other for charge) to make the parallel.

Although I said that some cells are not suitable for EUC use, these cells can be used in parallel with existing(and good) packs to increase mileage.

Ooo yes! :-D 

That is what I want to hear, I am very happy now! :-D 

Thanks again! 

[Jug]

As some of you guys know i builded Samsung INR18650-30Q 3000mAh - 15A 16S/ 2P battery pack, and in combination with my 16S/2P recycled laptop battery pack i have great autonomy.

But i want to build another one high end 16S/2P to parallel it with Samsung 30Q, so i need help from experts in this field @zlymex, @Keith, @esaj, @Jason McNeil, @Maxime and others knowers

The question is, since i have 3000mAh 15 Amps battery pack, Is it better to parallel it with 3500mAh 10 Amps like LG MJ1, Sanyo GA, Samsung 35E or with the same one i have Samsung 30Q? 

I am thinking to add more Ah 

[Jason McNeil]

@Jug from what I've read, it's not recommended to be mixing cell chemistries/types together in a pack, even if they're separate parallels.

[Jug]

4 minutes ago, Jason McNeil said:

@Jug from what I've read, it's not recommended to be mixing cell chemistries/types together in a pack, even if they're separate parallels.

@Jason McNeil, i will not mix the cells, i will not touch my 16S/2P Samsung 30Q, i just want to build up new 16S/2P to parallel it with existing Samsung 30Q 

[Jason McNeil]

Just now, Jug said:

i just want to build up new 16S/2P to parallel it with existing Samsung 30Q 

Even in parallel it's not ideal: each cell has a different discharge curve, so over the course of the discharge, each type of parallel pack will be taxed at different rates, which will not help cell longevity 
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