Spare battery connection

Steve Jessop

New Member
Hello, I have a Cube Kathmandu with a Bosch Performance CX motor with a 500w battery encased in the down tube. I used to have a Kreidler with the older type of Bosch motor and a 400w power pack battery that was fixed to the pannier. Sadly, my old bike was written off in an accident but the battery is still good. I was wondering if there is any way I could connect this old battery up to use as a spare on long tours? Preferably using the charging socket which is placed close to the motor?
Thanks, appreciate any expert knowledge/experience out there.
 

theemartymac

Active Member
I doubt the charging socket would work as it would be trying to pull the spare battery through the dead battery which is never good for batteries and will result in inconsistent voltage delivered to the controller as well. It also may not allow 'pass-through' power supply, and may shut off the controller output as soon as you add power to the charge port.

In theory, you can either open up the controller and splice in a parallel adapter and run closely matched batteries as one big one, or splice in a switch that allows you to choose Battery A or Battery B. The second choice is certainly the safer and easier of the two options as mismatching parallel batteries will result in uneven drain and shortened life.


 
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JES2020

Active Member
You could also match the discharge wires and just switch from the discharged battery to the back up battery...really simple to do.

Edit: If you don't have easy access to the discharge wires the job a little more complicated. However with a bit of creative intelligence you should be able to rig up something for a lot less money.

Just off hand, you could mock up a "dummy battery"(piece of wood and some wire), to slide into the down tube, which makes the connections and then patch your back up to that dummy(swap out). Does that make sense?
 
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David Berry

Well-Known Member
Region
Australia
City
Ipswich, QLD
Steve
I think Bosch is determined to stop endusers from doing what you would like to do.
David
 

JES2020

Active Member
Yep bosch has lots of proprietary parts and batteries is included.
The thing is no matter what shape the battery may be they all have a positive and negative terminal.
So even with proprietary batteries connections can be made to jump to another battery.
 

ki11a

Well-Known Member
The thing is no matter what shape the battery may be they all have a positive and negative terminal.
So even with proprietary batteries connections can be made to jump to another battery.
Wrong.

Alternatively, I'm willing to build my own entirely new batteries from scratch, but I don't know if the Go SwissDrive or Bosch computers and motors will play nice with a custom battery, even hooked up via their proprietary connectors. But if anyone has experience with that either, I'm very interested in your experience (especially if you succeeded :D). This is a no go for Bosch really since you need a Bosch BMS, however you could create a custom higher capacity battery and use the Bosch BMS maybe.

 

Steve Jessop

New Member
Thanks everyone for your help. At least know it is possible now. Any recommendations for the sort of place I should be looking to get a professional job done?
 

JES2020

Active Member
Wrong.



Wrong? Care to elaborate, or are you just being contradictory? It's obvious you would have to have a compatible BMS, if that's your major malfunction.
 

ki11a

Well-Known Member
Right, where are you going to get a genuine Bosch BMS? Its not just as simple as positive and negative terminals.


"Bosch is a closed system, no tampering. They usually use samsung cells (300wh pack). These you can open and you could connect the satiator to measure the capacity. However their later batteries are sealed and tamper proof. No one has ben able to repair them or make copies, yet. I have bought a few 300 and 400Wh packs that i will experiment on. Any knowledge about the bosh batteries pack are appreciated. i also buy them used/dead packs."

"I already repaired several batteries from Bosch without any problem, from the old type or the new one. But if the BMS is out, the battery won't work anymore and you will have to pay the 700€ to get a new one "

"There is authentication between the motor controller and the BMS and the battery does not supply power without handshaking being confirmed.
The only way to use this battery is to remove the BMS and use standard one, but then it will not work on the original system."

Again, NOT SO SIMPLE.
 
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tomjasz

Well-Known Member
Wrong? Care to elaborate
Many higher-end eBike builds have batteries that use a data cable. Rendering broad use impossible or out of the skill set of a majority of users. After all who will want to change a BMS and risk bricking a controller/display/BMS
 

JES2020

Active Member
Right, where are you going to get a genuine Bosch BMS? Its not just as simple as positive and negative terminals.


"Bosch is a closed system, no tampering. They usually use samsung cells (300wh pack). These you can open and you could connect the satiator to measure the capacity. However their later batteries are sealed and tamper proof. No one has ben able to repair them or make copies, yet. I have bought a few 300 and 400Wh packs that i will experiment on. Any knowledge about the bosh batteries pack are appreciated. i also buy them used/dead packs."

"I already repaired several batteries from Bosch without any problem, from the old type or the new one. But if the BMS is out, the battery won't work anymore and you will have to pay the 700€ to get a new one "

"There is authentication between the motor controller and the BMS and the battery does not supply power without handshaking being confirmed.
The only way to use this battery is to remove the BMS and use standard one, but then it will not work on the original system."

Again, NOT SO SIMPLE.
WRONG ...as I already stated, OBVIOUSLY you need a compatible BMS.
Reading is fundamental !
If you have other obvious arguments, that haven't already been addressed. feel free to try and educate me.
Also it might be useful to have a tiny bit of tact.
 

ki11a

Well-Known Member
Ah yes this mythical compatible BMS you keep referring to...Santa must be bringing it.

Not only did other users fail at this 'simple' task you keep referring to, you must know something everyone else doesnt!

and for a fact, you never stated you needed a compatible BMS, I DID, you said you could connect negative and positive terminals. LOL

The thing is no matter what shape the battery may be they all have a positive and negative terminal.
So even with proprietary batteries connections can be made to jump to another battery.
 

JES2020

Active Member
Ah yes this mythical compatible BMS you keep referring to...Santa must be bringing it.

Not only did other users fail at this 'simple' task you keep referring to, you must know something everyone else doesnt!

and for a fact, you never stated you needed a compatible BMS, I DID, you said you could connect negative and positive terminals. LOL
Do you understand the word obvious, I also didn't say the pack needed to have cells in it, I guess that one got by your sharp intellect ?
Do you have a battery that doesn't have a BMS.?.... brahahaha

I guess you are the one who thinks Bosch BMS's are a mythical device that can't be found ANYWHERE.

Anyway I grow tired of your crude attitude, so good luck with life.😎
 

ki11a

Well-Known Member
Ah yes instead of confirming your statements with any kinds of sources or links we MUST trust the know all.

I knew when I got messages about you being an idiot it was going to be a good laugh.
 

Steve Jessop

New Member
I never expected to start bike wars with this. However, I think I may have sourced the answer myself. Bosch actually offer a dual battery system which is available in multiple combinations of battery type and I believe this could be retro fitted.
 

JES2020

Active Member
I never expected to start bike wars with this. However, I think I may have sourced the answer myself. Bosch actually offer a dual battery system which is available in multiple combinations of battery type and I believe this could be retro fitted.
No worries. You didn't start it,
miserable people, trying to make others miserable . Seems to be more common in this political climate.
Anyway best not to associate with miserable people, so I just put them on ignore.
 

tomjasz

Well-Known Member
I never expected to start bike wars with this. However, I think I may have sourced the answer myself. Bosch actually offer a dual battery system which is available in multiple combinations of battery type and I believe this could be retro fitted.
It happens. One kit wonders that show up and use Google as their experience.