E8000 custom battery as a spare?

[Basy]

Has anyone built a custom battery for their Shimano E8000? I've been thinking about it because I'd like to build a spare that's a little bit smaller for possible trips back to the car when the main battery dies. Or a very small battery for shuttle days so I can still use my Di2 gears.

I assume it wouldn't be too hard as the likes of focus make their own integrated.. But not sure if anyone has made one yet?

Cheers

 

[Kernow]

Has anyone built a custom battery for their Shimano E8000? I've been thinking about it because I'd like to build a spare that's a little bit smaller for possible trips back to the car when the main battery dies. Or a very small battery for shuttle days so I can still use my Di2 gears.

I assume it wouldn't be too hard as the likes of focus make their own integrated.. But not sure if anyone has made one yet?

Cheers

I always think it would be good if I could use my Dewalt power tool batteries as an emergency or a top up for the odd ride that’s bit too far .
I guess for di2 you could use the normal di2 battery that’s fitted to ordinary bikes

 

[R120]

I am quite surprised no one has made a non OEM battery for the external steps mounts, i would be interested in a half size battery that was only 250/300wh and half the weight for quick blasts

 

[Basy]

I guess for di2 you could use the normal di2 battery that’s fitted to ordinary bikes

Yeah I thought about the Di2 battery (seat tube version) but it doesn't work with the E8000 system easily. Needs a different screen module and wiring etc.. I think I'd rather go back to cable derailleur..

I have a custom Bafang with a 52v pack. The packs aren't that hard to make which is why I'm suprised someone hasn't made one yet.

 

[ChrisB NZ]

I am quite surprised no one has made a non OEM battery for the external steps mounts, i would be interested in a half size battery that was only 250/300wh and half the weight for quick blasts

Yeah me too. Something that was half the weight and half the distance would be really useful for those bigger trips when you're not quite sure you will have enough range with one battery. Something that you could more easily carry in a back pack. Hopefully only a matter of time before someone does this.

 

[ldzielak]

I would expect you need the battery management smart to go along with custom battery? I haven't looked closely at my built in battery yet. But I'm already thinking of getting my hands on some Tesla 18650 cells and building a second pack and see how that goes as an experiment. I have 15yrs experience is high voltage LIPO batteries in large RC helicopters so a 10s pack with out battery management could be interesting too.

 

[Eckythump]

Problem with smaller packs is the cells having sufficient C rating to supply the amps required. You cannot get away from having the the correct number of cells in series as you need to keep the same overall voltage. If sticking with LiIon cells you could only really drop to 3 cells in parallel (like fitted to the Focus bikes). LiPo cells can provide far more current per cell but are heavier per watt hour.
As mentioned above the BMS is an issue too. I bought a RoPD connector to try and charge my bike using one of my RC chargers but couldn't get it to work. Seems the bike was waiting for a signal over the CAN Bus part of the connector before lining up the main power ports.
I have seen where folk have used a bottle rack/holder as a piggy back to the main battery they ran a parasitic line straight into the motor assembly.

 

[Eckythump]

Range extender for Levo has been brought up on here berfore. Same principal for tapping into E8000 setup....

Levo and Kenevo Battery Range Extenders

 

[njn]

Pretty there is a circuit to prevent non-shimano batteries. It would likely throw a E022 fault code.

If you have a failed battery pack, you could most likely replace the cells.

 

[ldzielak]

If anyone wanted to sell a failed or damaged pack, I could be looking to purchase and play. Other wise I may wire up a Lipo with a charger connector and build an emergency boost/charger for trail use. I know you can't use the bike while it's charging but it's better than having nothing.

 

[Hugh-Jazz]

Does anyone know what the two smaller terminals are on the Steps 8000 motor power connector? Are they CAN bus or a more simple connection to the battery?

 

[Dan63]

Does anyone know what the two smaller terminals are on the Steps 8000 motor power connector? Are they CAN bus or a more simple connection to the battery?

6V outlet for lighting.

 

[Hugh-Jazz]

Would splicing in a Shimano motor power cable to a 36V pack throw an error code on the controller? If the 6V is not provided, error?

 

[Kartman55]

Anyone using the 6v Shimano e8000 light output for other purposes: I used the 6v output (through a step-up converter) to power an array of lights (low and high beam turning with the fork, super high beam frame-mount, running, turn signals, always-on tail, and brake) plus charge my phone and trickle charge an auxiliary battery. But I learned that Shimano built logic into the motor that "flashes" the 6v output if you draw more than about 1A. I used a resistor to balance the load between the Shimano and accessory battery, and put cutoff switches on both sources.

 

[Kartman55]

I also put in two current/voltage panel meters to monitor what's happening.

 

[trailrider71]

Hi! Maybe one idea to make custom battery would be to buy Focus Jam2/Sam2 internal battery and modify this. At least it would have all necessary circuits so that you would not get any error codes for not being a Shimano battery.

 

[DrStupid]

Hi! Maybe one idea to make custom battery would be to buy Focus Jam2/Sam2 internal battery and modify this. At least it would have all necessary circuits so that you would not get any error codes for not being a Shimano battery.

Its ironic, that I found this thread, trying to figure out how to get rid of the Focus battery and charger from a jam2.

I'm looking for a Shimano compatible BMS, for a custom battery to stuff the downtube of a jam2.

Imho...It's only a matter of time before one (shimano compatible bms) are produced. There will be millions of these STEPS systems available to the DIY crowd very soon, as the first wave of ebikes go out of warranty and fail for whatever reason.

I can even imagine hopped up controllers and motors in the near future. I hope so!

 

[sdcoffeeroaster]

Its ironic, that I found this thread, trying to figure out how to get rid of the Focus battery and charger from a jam2.

I'm looking for a Shimano compatible BMS, for a custom battery to stuff the downtube of a jam2.

Imho...It's only a matter of time before one (shimano compatible bms) are produced. There will be millions of these STEPS systems available to the DIY crowd very soon, as the first wave of ebikes go out of warranty and fail for whatever reason.

I can even imagine hopped up controllers and motors in the near future. I hope so!

You might want to check the Focus section. A user bought a 152 wH battery pack made for a hover board with a BMS all about $50. and then wired it into a Rosenberger plug. It seemed to work except plugging it in instantly turned on the display....no button pushing required. Once it ran out after about 400 km of climbing he uplugged it and the normal battery still had a full charge. He rode with it but because of the unknowns, didn't use the data lines, we're not sure it's all that safe yet. It's not a nice water bottle size either but only weighs about 1 kg.

 

[jimbob]

It must be only a matter of time before someone makes an aftermarket battery. there must be money in it with the price the OEM ones are.

It also wouldnt suprise me if reconditioned batteries with new cells in start to appear soon. I hope so anyway!

 

[sdcoffeeroaster]

It must be only a matter of time before someone makes an aftermarket battery. there must be money in it with the price the OEM ones are.

It also wouldnt suprise me if reconditioned batteries with new cells in start to appear soon. I hope so anyway!

A premium LG 18650 battery like Focus uses is about $5. each. Less expensive and less capacity ones are used in the battery pack that I'm going to put together so you only get 158 wH out of 20 18650 batteries. The TEC pack and Jam2 have 30 batteries so there's $150. or so just in battery cost.

 

[jimbob]

Very true, although there will be a significant reduction if cells are bought in bulk. You can buy aftermarket powertool batteries of
~100wh for just over 30GBP, including housing, BMS etc. They wont be the same quality of course, but it does give a comparison.

For a second Ebike battery, if there was a choice of an aftermarket one for, say 50% of the OEM cost but with a 20% capacity reduction, im sure people would buy it.

 

[sdcoffeeroaster]

Very true, although there will be a significant reduction if cells are bought in bulk. You can buy aftermarket powertool batteries of
~100wh for just over 30GBP, including housing, BMS etc. They wont be the same quality of course, but it does give a comparison.

For a second Ebike battery, if there was a choice of an aftermarket one for, say 50% of the OEM cost but with a 20% capacity reduction, im sure people would buy it.

Yes I'm sure there is a market for light weight option. My bag and battery weigh 2 1/2 lbs and might give 10-15 miles range addition depending on how you ride and how much you climb. This battery I'm using only cost $34. I don't think I want to go into business though but I am a retired mechanical engineer and could do something like that with a big investment, lol. Just not what I'm after with this. No hiding that it's an ebike now!

 

[Acousticmood]

Anything new come to market since the last post?

 

[sdcoffeeroaster]

Anything new come to market since the last post?

LOL, I build my 125 wH pack that fits in an adjustable water bottle. I welded this one up myself too since I can't find anyone to build it for me. The pack itself is only 1 lb 3 oz. 10 cells. it's good for about 13+ miles in ECO so it's sort of an emergency backup for running on the native pack. And I can fit a shock with a reservoir again. I have another DVO on order since I stupidly sold mine, lol,

 

[Acousticmood]

I spent an hour scouring the internet and can’t find anything

 

[sdcoffeeroaster]

I spent an hour scouring the internet and can’t find anything

Looking for what an off the shelf range extender? I just bought a levo SL expert carbon so I'm getting out of the range extender side hobby and selling my Focus too.

 

[merlot]

Its ironic, that I found this thread, trying to figure out how to get rid of the Focus battery and charger from a jam2.

I'm looking for a Shimano compatible BMS, for a custom battery to stuff the downtube of a jam2.

Imho...It's only a matter of time before one (shimano compatible bms) are produced. There will be millions of these STEPS systems available to the DIY crowd very soon, as the first wave of ebikes go out of warranty and fail for whatever reason.

I can even imagine hopped up controllers and motors in the near future. I hope so!

Sorry for refreshing this thread.

Any Shimano compatible BMS in the market?

I'm looking for an aftermarket solution for the inner 378Wh battery of a Focus Jam2 since I don't want to buy another original one

Thanks