Can you fit an after market battery to a bosch equipped bike

[man1nvan]

I am after a cargo type electric bike, i like the bosch motor and i am a bit of a Gazelle fan. but all of the heavy duty gazelles have the battery under the rear rack, this uses up the space i normally fit my crate to so i wondered if i could get a down tube mount battery and hook it up to the rest of the system? i suspect not easily but just thought i would ask on here.

 

[vfr400]

I think it is possible as long as you keep the Bosch battery connected. The Bosch battery has the necessary handshaking protocols to allow the system to switch on and give power. You can splice a connector into the two main power wires, where you can bring a standard battery in parallel. There are some provisos though:

1. You must disconnect the standard battery and charge it independently.
2. It must be at the same voltage as the Bosch one each time you connected, which should be easy if you only connect when both aare fully-charged.

If you like messing about with electrics, you can make the process easier by using blocking diodes so that one battery can't charge the other through the discharge ports, then you can leave the second battery connected while you charge and not worry about matching voltages.

 

[man1nvan]

Thanks for the response with my level of electrical ability that is a no then that has saved me a few quid!

 

[Deleted member 16246]

I think it is possible as long as you keep the Bosch battery connected. The Bosch battery has the necessary handshaking protocols to allow the system to switch on and give power. You can splice a connector into the two main power wires, where you can bring a standard battery in parallel. There are some provisos though:

1. You must disconnect the standard battery and charge it independently.
2. It must be at the same voltage as the Bosch one each time you connected, which should be easy if you only connect when both aare fully-charged.

If you like messing about with electrics, you can make the process easier by using blocking diodes so that one battery can't charge the other through the discharge ports, then you can leave the second battery connected while you charge and not worry about matching voltages.

I wonder if there would be any mileage in transferring the Bosch BMS to the new battery. It might be a simple matter of just unplugging one BMS and plugging in the other. The BMS is almost certainly the thing that is communicating with the controller and the head unit.

I note that you caution about the parallel connection of two batteries. There have been some very nasty fires created by doing it when a full battery discharges rapidly into a low battery. There is one video from a youtuber in New York with a horrible fire outside his apartment - it was referenced on this website, and his setup had a bridge rectifier between the batteries, BUT - if it failed in short-circuit mode -expect fireworks. I think that is what happened in his case, although he was vociferously blaming the battery manufacturer.

 

[Nealh]

I wonder if there would be any mileage in transferring the Bosch BMS to the new battery. It might be a simple matter of just unplugging one BMS and plugging in the other. The BMS is almost certainly the thing that is communicating with the controller and the head unit.

No mileage at all if one bricks the BMS, Bosh BMS must be kept live all the time otherwise it is scrap.

 

[soundwave]

No mileage at all if one bricks the BMS, Bosh BMS must be kept live all the time otherwise it is scrap.

i thought this but it is not true but the bms must be working and charging for a recell to work but the bms wont work on gen 2 motors anyway.

 

[Deleted member 16246]

No mileage at all if one bricks the BMS, Bosh BMS must be kept live all the time otherwise it is scrap.

How could that work? You are suggesting that the BMS destroys itself if it loses power. If so, how could you build the thing in the first place? I suppose it could work if the avr which controls it was programmed without any permanent storage of its firmware - flashed after the battery was build and the BMS connected, but the company would be building a ridiculous weakness into their batteries and lining up reputational damage and warranty claims.

 

[soundwave]

How could that work? You are suggesting that the BMS destroys itself if it loses power. If so, how could you build the thing in the first place? I suppose it could work if the avr which controls it was programmed without any permanent storage of its firmware - flashed after the battery was build and the BMS connected, but the company would be building a ridiculous weakness into their batteries and lining up reputational damage and warranty claims.

from gen 2 the batts motors and displays use a can bus system to talk to each other so most thought there was a chip on the bms that if it lost power it would loose its data and be rendered useless but this is not the case it turns out and can be done if the bms is good to go.

now if you have one of them power tube batts that goes in to the frame they cant be recelled just because of the way they are designed and force you to buy a new one and throw it in the bin same as apple ect.

my original frame batt gen2 400w is still working but is now way down on range and will not even do 10 miles in turbo mode but will be able to recell it.

 

[Deleted member 16246]

Fascinating videos there Soundwave. Nothing like over complicating the construction and operation - eh? The second one is fit only for salvage of the cells. Especially interesting that the supposed top line battery was put together with pinched wires that were almost short circuited. Maybe you don't always get what you pay for after all....

Hopefully, you will succeed in re-celling the battery you want to refurbish, as long as the electronic parts are functional. This canbus stuff seems a bit over the top. I am not sure what extra functionality the user gets through its inclusion in the battery. It may make it more difficult to repair outside the original manufacturer's supply chain though. 'Sorry Sir. New £800 battery required. Only obtainable from us.'

Makes me glad I have a generic kit conversion bike myself. I hate Apple for the same reason. Fit your own battery and the thing refuses to work. Meanwhile, Apple sucks up billions from its eager fans.

Thanks for sharing.

 

[soundwave]

they use can bus to stop you using other batts other than bosch ones otherwise the motor will not turn on unless they talk to each other.

jimmy can recell the bosch frame and rack batts and custom build packs as well for other motors to use

eBike Batteries

ebikebatteries.co.uk

 

[jimriley]

I wonder what effect the coming "right to repair" laws will have on Bosch motors and batteries?

 

[soundwave]

peter at performance line bearings can fix most things motor wise and is a bosch dealer also but alot of the motors have shorted controller boards inside the motors from water ingress and bosch dont sell those parts to anyone at the moment.

i have some genelec speakers that need a refoam kit for one of the mid drivers but genelec wont sell me a £2 piece of foam and id have to buy a HOLE NEW DRIVER that cost £600+vat and postage.

now if it was any other driver i can get a kit for them just not a genelec 5inc driver as custom made for them and nothing else will fit.

 

[KeithMac]

I wonder what effect the coming "right to repair" laws will have on Bosch motors and batteries?

Probably not a lot, if you've ever worked on modern cars they are all CanBus controlled, Dealer Software required for flashing modules etc. That's not going to change.

They can't expect Bosch Cycle division to work to a completely different set of rules to Bosch Automotive imho.

Just look at Apple, all their new phones nearly every component is keyed, can't even replace a camera as they are married from the factory.

 

[Deleted member 16246]

Probably not a lot, if you've ever worked on modern cars they are all CanBus controlled, Dealer Software required for flashing modules etc. That's not going to change.

They can't expect Bosch Cycle division to work to a completely different set of rules to Bosch Automotive imho.

Just look at Apple, all their new phones nearly every component is keyed, can't even replace a camera as they are married from the factory.

I have systematically avoided buying Apple products all my life because of their grasping model of business. Top prices and maximum control over what the user can do with their own product.

 

[Croxden]

I have systematically avoided buying Apple products all my life because of their grasping model of business. Top prices and maximum control over what the user can do with their own product.

But they work though.

 

[KeithMac]

I have systematically avoided buying Apple products all my life because of their grasping model of business. Top prices and maximum control over what the user can do with their own product.

Yep same here, Samsung for me (Android) all day long.

 

[wheeler]

But they work though.

True, but only in the way that Apple allows which is not necessarily the way that the owner of the device wants.
Typical examples of Apple's "we know best how you will use our product" attitude is the refusal to allow micro-sd card memory expansion and usb charging instead of the proprietary lightning connector.

 

[Ocsid]

Typical examples of Apple's "we know best how you will use our product" attitude is the refusal to allow micro-sd card memory expansion and usb charging instead of the proprietary lightning connector.

Surely that is to facilitate their further exploitation of their main income stream, their clients?

 

[soundwave]