New bike, new motor, new cells, new project !!

[MamboN5]

Wow! Build a lighter battery compatible with the 750wh powertube battery and you have a new customer
Good Luck!

I don't manufacture batteries professionally; it's just a hobby. This post is for sharing knowledge so we can all contribute to the common good. The next step, for example, is uncharted territory for me: the internal components of a Bosch battery and its BMS. If anyone has experience with this system, I'm very interested to know if I'll have problems disconnecting the BMS from the cells. I didn't have any problems with the TQ battery, but I've read that some systems, when the BMS is disconnected from the cells, don't reconnect properly for safety reasons.

 

[KuRi]

I don't manufacture batteries professionally; it's just a hobby. This post is for sharing knowledge so we can all contribute to the common good. The next step, for example, is uncharted territory for me: the internal components of a Bosch battery and its BMS. If anyone has experience with this system, I'm very interested to know if I'll have problems disconnecting the BMS from the cells. I didn't have any problems with the TQ battery, but I've read that some systems, when the BMS is disconnected from the cells, don't reconnect properly for safety reasons.

That's awesome anyway. I also have doubts that the BMS will allow for easy cells replacement, but I wish you the best of luck. I have been searching for years how to do something similar with the original Orbea Rise 360wh internal battery to increase capacity, but found nothing.

I am also from Spain, and I also have an ebike with the 750wh power tube internal battery. Let me know how can I help

 

[MamboN5]

That's awesome anyway. I also have doubts that the BMS will allow for easy cells replacement, but I wish you the best of luck. I have been searching for years how to do something similar with the original Orbea Rise 360wh internal battery to increase capacity, but found nothing.

I am also from Spain, and I also have an ebike with the 750wh power tube internal battery. Let me know how can I help

Changing the cells isn't a problem since the BMS has no way of knowing where the voltage is coming from. As you probably know, in Spain there are extender manufacturers who connect their extender inside the battery before the BMS for it to work. We already know that neither the Bosch BMS nor the TQ BMS, nor any other, can know where the voltage is coming from. The only thing we might encounter is that it might lock up if we disconnect it from some cells and leave it without power. There's a solution for that too, but it complicates the cell-changing operation. The new cell pack would have to be connected without disconnecting the old one. I'll have to experiment with the battery I bought. Being in Spain makes it easier to replicate what I do. In fact, I used to post my projects on the Spanish forum, but I didn't like the way the forum owner behaved and decided not to contribute any more content.

 

[cream]

I don't manufacture batteries professionally; it's just a hobby. This post is for sharing knowledge so we can all contribute to the common good. The next step, for example, is uncharted territory for me: the internal components of a Bosch battery and its BMS. If anyone has experience with this system, I'm very interested to know if I'll have problems disconnecting the BMS from the cells. I didn't have any problems with the TQ battery, but I've read that some systems, when the BMS is disconnected from the cells, don't reconnect properly for safety reasons.

I have some experience with servicing Bosch batteries. I didn't see their latest products internally, but from their first system (classic) up to (including) Powertube 750Wh smart they won't lock the BMS when you disconnect them. Worst case, it will register an error that every Bosch dealer can clear with their diagnostic tool. Also, moving the BMS to a higher capacity pack might work with Bosch. I've tried mounting a 400Wh Powerpack BMS to a 500Wh rebuilt pack. It worked, more than that, calibrated itself for extra capacity and let me used the whole 500Wh after a complete cycle.

So in this regard, you're in a bit of luck. Other manufacturers will firmware lock the BMS once you disconnect it and also won't let you use extra capacity unless it's programmed in firmware (eg. Specialized, Fantic, Orbea, Shimano, Yamaha etc).


Good luck with your project, I'm curious how it will turn out. As long as you design a proper case for the battery pack, I think your project will succeed, at least as a working prototype. I did something similar for Specialized/Brose motor and there were some obstacles along the way ) But it turned out just like I wanted.

 

[MamboN5]

I have some experience with servicing Bosch batteries. I didn't see their latest products internally, but from their first system (classic) up to (including) Powertube 750Wh smart they won't lock the BMS when you disconnect them. Worst case, it will register an error that every Bosch dealer can clear with their diagnostic tool. Also, moving the BMS to a higher capacity pack might work with Bosch. I've tried mounting a 400Wh Powerpack BMS to a 500Wh rebuilt pack. It worked, more than that, calibrated itself for extra capacity and let me used the whole 500Wh after a complete cycle.

So in this regard, you're in a bit of luck. Other manufacturers will firmware lock the BMS once you disconnect it and also won't let you use extra capacity unless it's programmed in firmware (eg. Specialized, Fantic, Orbea, Shimano, Yamaha etc).


Good luck with your project, I'm curious how it will turn out. As long as you design a proper case for the battery pack, I think your project will succeed, at least as a working prototype. I did something similar for Specialized/Brose motor and there were some obstacles along the way ) But it turned out just like I wanted.

Thank you so much for the information, it's invaluable to me right now. I did find a cheap 750Wh battery, but a 600Wh one would surely have been even cheaper. And now, knowing that capacity changes are possible, it's a bit easier for anyone wanting to replicate the experiment.

 

[cream]

That's awesome anyway. I also have doubts that the BMS will allow for easy cells replacement, but I wish you the best of luck. I have been searching for years how to do something similar with the original Orbea Rise 360wh internal battery to increase capacity, but found nothing.

Also serviced some Orbea Rise batteries (BMS side). Can't remember if the cells are 18650 or 21700 but in any case, it's possible (in theory) to build a larger capacity pack in the same original case.
The same battery chemistry can be packed into a pouch cell or a cylindrical cell, each package with pros and cons. Lately, manufacturers started to use advanced chemistries in cylindrical format (21700, even 18650) so it's possible, in theory, to upgrade the cells on most ebike batteries. Most ebike battery pack manufacturers up to present usually use battery tech from 5-7 years ago. Availability, trust in new tech and price might play a role in that. DJI might be an exception

For example, LG MJ1 cell was a popular choice among major pack manufacturers. That cell tech is from 2015-2016 but still in production today and some manufacturers still use them.

 

[cream]

Thank you so much for the information, it's invaluable to me right now. I did find a cheap 750Wh battery, but a 600Wh one would surely have been even cheaper. And now, knowing that capacity changes are possible, it's a bit easier for anyone wanting to replicate the experiment.

I only shared my experience. I can't generalize based on that. Newer BMS models might behave differently. For example, Smart dealer app is a step backward in what it's called a diagnostic app. It will show less information (diagnostic data) so it will be harder for me (or people who diagnose an ebike system) to know what's going on. Real testing on those systems would get you certainty

 

[KuRi]

Also serviced some Orbea Rise batteries (BMS side). Can't remember if the cells are 18650 or 21700 but in any case, it's possible (in theory) to build a larger capacity pack in the same original case.
The same battery chemistry can be packed into a pouch cell or a cylindrical cell, each package with pros and cons. Lately, manufacturers started to use advanced chemistries in cylindrical format (21700, even 18650) so it's possible, in theory, to upgrade the cells on most ebike batteries. Most ebike battery pack manufacturers up to present usually use battery tech from 5-7 years ago. Availability, trust in new tech and price might play a role in that. DJI might be an exception

For example, LG MJ1 cell was a popular choice among major pack manufacturers. That cell tech is from 2015-2016 but still in production today and some manufacturers still use them.

I know a lot of customers that would pay for an increase battery capacity on 2021 orbea rise carbon. Even 540wh would be enough.

I tell you in case you want to try

 

[MamboN5]

I know a lot of customers that would pay for an increase battery capacity on 2021 orbea rise carbon. Even 540wh would be enough.

I tell you in case you want to try

The first step would be to know the battery's dimensions, how much free space is left inside the frame, and if possible, the next step would be to open the battery and see, as the colleague mentioned, which cells it contains. With that data, we could see if simply changing the cell model would increase our autonomy, and if not, we could consider manufacturing the pack with semi-solid cells like the ones I'm going to use. The tricky part is bypassing the safety precautions the colleague mentioned and performing the entire operation without the BMS losing voltage at any point.

 

[cream]

I tell you in case you want to try

For now I'm already engaged in other projects and don't have the time for it. Maybe in the future, as a joint project. Somebody would manufacture the case/cell assembly, I could take the BMS needed modification, design the nickel plates and so on. Making a proper Li ion pack is not a trivial task. Like all things made right. Even french fries Did I forgot about coffee?

 

[MamboN5]

With the best current cells, you could reach 396 Wh, and the other option with semi-solid cells would be to try to fit two sets of 8.3 Ah cells, measuring 7x50x130 mm and weighing 100 g each, into that space to achieve a 597 Wh battery. But the available space is very limited to fit all those cells plus the BMS, etc. It's a good challenge; I'd probably have to resort to using space inside the frame that the original battery wasn't using, just like I had to do with the Trek Fuel EX.

 

[KuRi]

With the best current cells, you could reach 396 Wh, and the other option with semi-solid cells would be to try to fit two sets of 8.3 Ah cells, measuring 7x50x130 mm and weighing 100 g each, into that space to achieve a 597 Wh battery. But the available space is very limited to fit all those cells plus the BMS, etc. It's a good challenge; I'd probably have to resort to using space inside the frame that the original battery wasn't using, just like I had to do with the Trek Fuel EX.

597 would be a dream

I had access to a defective battery for 150€ but I did not buy it because I was not sure it this could be done and now is gone

 

[MamboN5]

We now have the 750 powertube battery ready to be disassembled; the first challenges lie ahead.

 

[KuRi]

Go Go Go! I believe in you

 

[Christian050567]

Thank you for the update on this interesting project.
What is that circuit board in the last two photos? Does it come from the battery? Wouldn't the BMS also be stored on it? I understood from the previous posts that the BMS must always be supplied with power. That doesn't seem to be the case here. Isn't that necessary anymore?
Thank you for a short reply and best regards,
Christian

 

[cream]

Thank you for the update on this interesting project.
What is that circuit board in the last two photos? Does it come from the battery? Wouldn't the BMS also be stored on it? I understood from the previous posts that the BMS must always be supplied with power. That doesn't seem to be the case here. Isn't that necessary anymore?
Thank you for a short reply and best regards,
Christian

That's not a requirement for Bosch BMS. But on other manufacturers, the firmware on the BMS can lock, preventing further use. But even so, there are ways to prevent locking when disconnecting the BMS board from the battery pack.

 

[Christian050567]

That's not a requirement for Bosch BMS. But on other manufacturers, the firmware on the BMS can lock, preventing further use. But even so, there are ways to prevent locking when disconnecting the BMS board from the battery pack.

Thank you very much!

 

[Christian050567]

Dear MamboN5,
are there any news in your interesting project? I am thinking of doing something similar with a Fazua battery but want to wait until you finish your project. I want to learn first from your solutions.
Thank you and best regards
Christian

 

[MamboN5]

Dear MamboN5,
are there any news in your interesting project? I am thinking of doing something similar with a Fazua battery but want to wait until you finish your project. I want to learn first from your solutions.
Thank you and best regards
Christian

Hello, I'm currently very busy with work and have little time to dedicate to the battery. At the moment, I have the BMS disassembled. The next step is to disassemble the cell pack to extract the temperature and voltage sensors. Once I have all the components, I need to disassemble the bike to measure the battery mounting points. With all this information, the complete battery design will be created. I will keep you updated on the progress.