Two batteries on one bike :)

[MrMark]

Hi,
I want to increase my ebike range. I have bbs02b middrive motor and 17.5ah 48v battery attached to a bike frame. I think about getting second one on a back rack. Can you recommend me UK supplier of these? Should I buy them from Amazon? Can anyone recommend me a good rack for that cargo?
Cheers

 

[Raboa]

Hi, I have asked bmsbattery if they can make me another battery at the same time as recelling my current one.

I will be putting it my pannier.

Here is a link to rack recommendations.

Best bike pannier bags and pannier racks 2025 — our ultimate guide to all your cycling luggage possibilities

Are bicycle panniers the best way to carry stuff? They certainly can be, depending on your bike and individual needs. In this guide, we'll take a look at your bike luggage options and help you choose from the best panniers and pannier racks available.

road.cc

Hope this helps.

 

[jarob10]

Here’s one I did earlier

It can actually take 2 batteries on the rear rack, so 3 in total

There's a mid drive & rear hub motor fitted - v powerful & mega range, but doesn't feel much like a bike sadly

 

[MrMark]

Wow impressive mate
Where did you buy batteries from? Does anyone know any good UK supplier of 48v rack batteries?

 

[jarob10]

My original rack battery was from ebike conversions in stoke. I got a duplicate rack battery from aliexpress. The original stoke battery was fitted to a bike that was stolen a couple of years ago

 

[Nealh]

On my 700c Boardman I carry three PF batteries, one on down tube and a pair of soft packs in the rear top bag. Paralleled all together for 10s14p for 40.6ah/1461 wh @36v nom. 160 odd miles at usage of 9wh/m.

 

[MrMark]

I need to get a proper rack for battery. I have wheels in size 700c and on top of the rack I'm going to carry a cargo in backpack up to 12kg so it has to be very durable. Any idea where I can get one? It has to be able to fit a battery of course.
How you guys connect all these batteries to yours bikes?

 

[Nealh]

I run the power supply leads from the controller to my top rack bag and fit a XT90 antispark connector. Then I run my down tube battery power supply to the rack bag and fit a XT60 to the end which matches the XT60 on my other two battery packs in the rack bag. To connect them all up as one I solder up a 3T1 parallel lead, the three tails for battery connection each have an XT60 to mate with the batteries and the other end has an XT90 to mate with the controller connection.

When soldering up a parallel lead you have to make sure that all Black wires are soldered together on one side of the connector and all the Red wires are soldered on the other, if you get it wrong and wire up in series then bang you will blow the controller or possibly melt connectors or wiring.

2T1 parallel lead.


3T1 parallel lead.


Wiring is 14awg 32amp rated continuous.
XT60 60a rated continuous.
XT90 90A rated continuous.