Giant battery DIY upgrade

[Nobrks]

Has anyone exchanged cells in Giant battery pack?
I have org. Giant 625Wh batteripack 10p5s 18650 weighting 4,3kg
that I would like to modify to 10p2s, 1,6kg 400Wh 21700 4900mA Samsung E50 cells. With custom battery housing and mount it to the frame through the extra hole in the frame. (Will be alot shorter pack as well).

This would bring my Reign e+0 down to 22,3kg with exo+ tires and pedals.

My biggest concern is if the BMS will not like the diffrent cells ??

Any comments or recomendations appriciated!

 

[UnreasonableMuppet]

Interested to see how this goes.

 

[Waynemarlow]

Interested to see how this goes.

Won’t go or only very slowly, the Samsung E50 cells are only good for about 5amps max @ max volts, the voltage sag will trigger the BMS.

The Samsung 40T will be fine up to about 500W’s but have less capacity.

The other concern is keeping the BMS alive whilst transplanting the cells, wasn’t there already a thread about this a few years back ?

 

[Nobrks]

Won’t go or only very slowly, the Samsung E50 cells are only good for about 5amps max @ max volts, the voltage sag will trigger the BMS.

The Samsung 40T will be fine up to about 500W’s but have less capacity.

The other concern is keeping the BMS alive whilst transplanting the cells, wasn’t there already a thread about this a few years back ?

Thanks for sharing.
The E50 is rated 9,5A, but if real performance is 5A then I would need 3 and not 2 cells together, and limited max power
Keeping the bms alive? Will it go into error mode without power ?

I have a second battery pack, that could fetch voltage from, but it would be scetchy too work on
Good question, is if pack voltage is enough, or if BMS needs voltage on each cell section during rebuild?

FYI the alu battery casing is almost 900gr on 625wh

 

[Waynemarlow]

Yup you will need 3P at least, check this thread out.

Can you build your own battery for the E10 ?

Yes is the answer, but with caveats here. The manufacturers use proprietory Can Bus signals and the likes to manage and interpret the battery to protect it from too much load and the total number of charges etc. But if you research and look around the internet its surprising how much info you...

www.emtbforums.com

I'm not sure about the Giants battery and letting the BMS go cold other than reading a long time ago a thread where the poster had not done so and the battery BMS had failed to reboot. He was a very very clever guy and had some how worked out how to patch the BMS and had got around the problem. Its out there somewhere on the internet.

Certainly on the Fazua battery I replaced the cells in, I had no luck as the BMS had already drained the first two sets of cells below the cells thresholds and damged them enough to also depower the BMS. Dumb electronics design but stops the battery boys recelling defunct batteries I guess. Even worse is that the Fazua charger has what looks like a CAN command before it will allow a charger to charge the battery.

 

[TQFreak]

If this Giant uses Yamaha motor there is a dongle mod allows you to use any DIY battery with Yamaha motor. You basically build new battery pack or rebuild the original pack with new cells, throw away the original BMS, put regular BMS and put this dongle.

By the way you might need no any dongle mod, according to the information from the link below Giant does not use battery manufacturer protection on their batteries with Yamaha (Syncdrive) motors and you can use any battery with same voltage as the original one. If the original Giant battery has rebuild protection, just throw away the original BMS from the battery and put regular BMS instead

Yamaha mid-drive motor dongle to use 3rd party batteries

Here, I share technical solutions that arised during the development of my solar-bike.

www.avdweb.nl

 

[Nobrks]

If this Giant uses Yamaha motor there is a dongle mod allows you to use any DIY battery with Yamaha motor. You basically build new battery pack or rebuild the original pack with new cells, throw away the original BMS, put regular BMS and put this dongle.

By the way you might need no any dongle mod, according to the information from the link below Giant does not use battery manufacturer protection on their batteries with Yamaha (Syncdrive) motors and you can use any battery with same voltage as the original one. If the original Giant battery has rebuild protection, just throw away the original BMS from the battery and put regular BMS instead

Yamaha mid-drive motor dongle to use 3rd party batteries

Here, I share technical solutions that arised during the development of my solar-bike.

www.avdweb.nl

No sure about the syncdrive 3x, but previous versions have had Giant motor-controller in the Yamaha motor, with locked canbus communication to the battery.
But I guess the only way to find out, is to try it.

 

[Nobrks]

Project died because, 625wh I got was not working, not charging and not turning bike ON, even though it had 40% charge.

Soulution was to make the 800pack lighter with new battery case, 500g lighter. 3D print CF and 1x layer of aramid/CF

From factory the 800 pack is really tight in the housing, so plastic bag had been rupturen in factory during assembling, and one wire was close to short circuit to housing as part of wire insulation was scraped off(brand new battery) .
I dissasemblrd battery in the oposide direction it had been assembled, so I was not in doubt of origin of damage.

 

[Regular_Michael]

Project died because, 625wh I got was not working, not charging and not turning bike ON, even though it had 40% charge.

Soulution was to make the 800pack lighter with new battery case, 500g lighter. 3D print CF and 1x layer of aramid/CF
View attachment 106930 View attachment 106931
From factory the 800 pack is really tight in the housing, so plastic bag had been rupturen in factory during assembling, and one wire was close to short circuit to housing as part of wire insulation was scraped off(brand new battery) .
I dissasemblrd battery in the oposide direction it had been assembled, so I was not in doubt of origin of damage. View attachment 106932

Nice job - are you selling the STL files by any chance?