Any advice on generic/DIY range extenders for Brose motor?

MobyRick

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Hi all. I'm new here.

I've got a Rockrider EST900 but the range is dissapointing. I live in Northumberland and when I'm out in the hills I don't get much more than 20 miles. I don't want to spend a lot of money on a second Decathlon battery. I'd prefer a DIY/generic range extender battery that is ideally cheap, simple to fit, removable and not too big or heavy. I've only come across a couple that might fit the bill:

Woosh bag battery 36V 10AH - E-bike Batteries from Woosh - I could either fit this to the seatpost or strap it to the frame/rack.

UPP bottle battery 36V 7AH - 【CN STOCK】36V 7Ah BMS20A 18650 LG3500mah Cells mini 2 layers Bottle Ebike battery For 0-250W Motor/Ship from China - Unit Pack Power - This is the only bottle battery I've found small enough to fit my frame (It's a small bike with a big battery)

Alternatively I suppose I could strap a second battery to the pannier rack, but that's not ideal. I don't want to always keep the rack on.

I can access the wires in the motor and I'm happy to do a bit of soldering if necessary. I know I'll need a balancer/ideal diode so both batteries charge in parallel. But I haven't done this before and I don't want to give the impression that I know what I'm doing!

I was just wondering if any of you guys have added DIY range extenders like this, or if you have any advice or thoughts?

Thank you!
 
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Hi all. I'm new here.

I've got a Rockrider EST900 but the range is dissapointing. I live in Northumberland and when I'm out in the hills I don't get much more than 20 miles. I don't want to spend a lot of money on a second Decathlon battery. I'd prefer a DIY/generic range extender battery that is ideally cheap, simple to fit, removable and not too big or heavy. I've only come across a couple that might fit the bill:

Woosh bag battery 36V 10AH - E-bike Batteries from Woosh - I could either fit this to the seatpost or strap it to the frame/rack.

UPP bottle battery 36V 7AH - 【CN STOCK】36V 7Ah BMS20A 18650 LG3500mah Cells mini 2 layers Bottle Ebike battery For 0-250W Motor/Ship from China - Unit Pack Power - This is the only bottle battery I've found small enough to fit my frame (It's a small bike with a big battery)

Alternatively I suppose I could strap a second battery to the pannier rack, but that's not ideal. I don't want to always keep the rack on.

I can access the wires in the motor and I'm happy to do a bit of soldering if necessary. I know I'll need a balancer/ideal diode so both batteries charge in parallel. But I haven't done this before and I don't want to give the impression that I know what I'm doing!

I was just wondering if any of you guys have added DIY range extenders like this, or if you have any advice or thoughts?

Thank you!
* I meant discharge in parallel, not charge!
 
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