Custom battery for Bosch Gen 4, Shimano EP801, Specialized(Brose) motors feasibility?

[scm007]

Before I purchase my ebike I want to make sure that these motor systems will take a custom battery charged to the correct voltage. Essentially I'm going to build N x 100wH batteries (probably 6) so that I can make it TSA legal and fly with it, reassembling the battery when I land.
1.) Do these motors have some special software interface with their proprietary batteries that will prevent it from running even if a properly charged battery is connected?
2.) Do any of these motor systems support connecting batteries through the charging port so that this could be an external battery?

Any other thoughts?

 

[ebsocalmtb]

Before I purchase my ebike I want to make sure that these motor systems will take a custom battery charged to the correct voltage. Essentially I'm going to build N x 100wH batteries (probably 6) so that I can make it TSA legal and fly with it, reassembling the battery when I land.
1.) Do these motors have some special software interface with their proprietary batteries that will prevent it from running even if a properly charged battery is connected?
2.) Do any of these motor systems support connecting batteries through the charging port so that this could be an external battery?

Any other thoughts?

they will essentially not take a custom battery. So to answer your questions:
1) yes, it's in the bms
2) depends on which bike, but again, it's bms dependent.

There are some people that have accomplished this on some motors with mixed results. Some successes but with some caveats such as the bike not knowing exactly what the capacity/status of the battery and thus showing not real %'s remaining. All the way to not working consistently.

One thing is for sure, it will require harvesting the bms out of an existing battery that is compatible (in your case, multiples), and then plowing forward and praying.

As someone whom has fiddled around with building my own batteries for bafang/tsdz2 conversions and would love to do this for my own oem built turn key emtb's... the answer for me is no. I know enough to do it in theory, but the uncertainty of the bms compatibility and the locked nature of the firmware on these motors is enough to stop me from trying.

It's one of those situations where if you have to ask, you likely don't know enough and aren't ready to plow forward down a path with absolutely no historical information or guides to accomplish it. On the flip side, provided you have the right scopes/tools (I'd estimate that I'd need about 500-700 of equipment to do it right) and have an absolute crap load of free time and patience, it could feasibly be done.

If i were truly hell bent on flying with my ebike, I would buy a transition relay and take the battery out and ship it to my hotel. Still not kosher or legal as you can't technically ship a battery with this much capacity via ups... but it would be the most feasible way to accomplish this.

 

[Ura]

and if an additional self-made battery, connect it instead of a charger? and go like that? original batteries are expensive, self-made ones are three times cheaper

 

[arildl]

Not only do most major brands have proprietary interfaces to make things complicated for DIY. I tried to repair a Shimano-bike battery at a specialist shop - and they told me there are brands out there making the BMS self destructive if they loose power. Which means that if you dissassemble the battery - the BMS will self destruct and will not work after assembly again.

If you convert an old bike to ebike with the Bafang BBS02 (maybe others also), you only need a 36V battery and you can make n*100Wh batteries and rebuild them after flight. But you will then miss out on the moment-sensor. I would rather rent a bike after a flight than bringing a bike with the old BBS02 motor.