Adding second battery

[muzzammil nadeem]

Hi i have a halfords assist bike i want to add a second battery for range anyone in Huddersfield that does the conversion please

 

[Az.]

Why are you looking for somebody who does conversions? All you need is to mount second battery somewhere on your frame and swap them when needed.

 

[thelarkbox]

+1 to the above, the 20-30 seconds it takes to swap a battery over is a very minor inconvenience compared to the risks and expense of connecting two batteries together, also simply not carrying the 2nd battery when not needed is easier when you have no need to keep 2 batteries in an identical state

 

[Deleted member 16246]

+1 to the above, the 20-30 seconds it takes to swap a battery over is a very minor inconvenience compared to the risks and expense of connecting two batteries together, also simply not carrying the 2nd battery when not needed is easier when you have no need to keep 2 batteries in an identical state

I've never done this but I have seen some worrying videos about the risks that can come from connecting two big batteries in parallel. I only mention this to add to your warning tone here.

As I understand it, you can create a huge current flow between the two batteries if they are at different charge levels. I first came across this risk when watching a video about ebike fires. The presenter was warning against the practice of amateurs rigging up such arrangements and was illustrated by film of a burned out N. York apartment where someone had attempted this idea.

 

[matthewslack]

I always include a fairly small value fuse (10A or less) in the interconnecting wiring, as well as only performing the connection at equal voltage. Belt and braces.