36V (3x12V) Pb battery replacement

Batteries, Chargers, and Battery Management Systems.
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nuxland   100 W

100 W
Posts: 210
Joined: Apr 04 2015 2:18pm
Location: Tallinn
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36V (3x12V) Pb battery replacement

Post by nuxland » Sep 12 2020 5:17am

Got one old scooter to my son who is going to university. But it had 3x12V 12Ah Pb battery inside that only allowed around 12km of range. And the charger was 1,5A, so 8h to fully recharge again.
Goal was to put the replacement battery to the same place so I had size restriction. After calculation I sourced 120pcs of "Samsung INR18650-35E 3450mAh - 8A - refurbished" and configured it in 12p10s. nkon holders if combined to 8x15 arrangement were a little to big so bough from aliexpress ready made one pice 8x15 holder and also bough from the same place 6p wide nikkel. As 12p 8A cells can give over 100A but I only needed 30A (that is what brushed motor and 1kw dc controller was rated for) I bought 60A BMS from aliexpress because these were still in the right size. If you go over 80A or 100A they are to large.
This was my first time to use welder that was sitting in shelf from year 2017 :)
Used 100Ah car battery because my lipos were 7s and that is to high for welder mosfets.
36V_40Ah_Weld_Begin.jpg
36V_40Ah_Weld_Begin.jpg (397.83 KiB) Viewed 364 times
Added second layer nikkel where there was only 3 ribbon in series
36V_40Ah_Weld.jpg
36V_40Ah_Weld.jpg (290.61 KiB) Viewed 364 times
BMS installed and output wires done
36V_40Ah_BMS.jpg
36V_40Ah_BMS.jpg (299.87 KiB) Viewed 364 times
New Battery weight without bag and padding (add few hundred grams)
36V_40Ah_Weight.jpg
36V_40Ah_Weight.jpg (264.19 KiB) Viewed 364 times
Old Pb Battery weight
36V_12Ah_Weight.jpg
36V_12Ah_Weight.jpg (229.2 KiB) Viewed 364 times
Testing is it working before shrinkwrapping
36V_40Ah_Testing.jpg
36V_40Ah_Testing.jpg (261.76 KiB) Viewed 364 times
Shrink wrapping (also added extra balance wire just in case when I want to charge it with my 4010 duo)
36V_40Ah_ShrinkWrap.jpg
36V_40Ah_ShrinkWrap.jpg (264.33 KiB) Viewed 364 times
Ready and installed in bag. Only difference from outside is XT90 connector
36V_40Ah_Ready.jpg
36V_40Ah_Ready.jpg (153.63 KiB) Viewed 364 times
In Calculations scooter should have now 4 times the range and battery is 5kg lighter.
Bought also 42V and 5A aliexpress charger to be able to charge it in 8h when empty.
Electric kart 60kw: viewtopic.php?f=34&t=68543
100v 35Ah LiPo battery: viewtopic.php?f=14&t=97763
100v 25Ah LiFePo4 battery: viewtopic.php?f=14&t=85912
Scooter battery: viewtopic.php?f=14&t=108227#p1582703

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nuxland   100 W

100 W
Posts: 210
Joined: Apr 04 2015 2:18pm
Location: Tallinn
Contact:

Re: 36V (3x12V) Pb battery replacement

Post by nuxland » Jan 01 2021 6:58am

Made another one and now have two of these.
Attachments
36V_40Ah_SecondOne.jpg
36V_40Ah_SecondOne.jpg (346.68 KiB) Viewed 117 times
Electric kart 60kw: viewtopic.php?f=34&t=68543
100v 35Ah LiPo battery: viewtopic.php?f=14&t=97763
100v 25Ah LiFePo4 battery: viewtopic.php?f=14&t=85912
Scooter battery: viewtopic.php?f=14&t=108227#p1582703

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