Kids, eh?

[Gary]

My 9yr old daughter just asked me a pretty valid question about my Ebike I couldn't answer?

Why is the charger for it so big?
(Shimano E8000)

 

[Norange]

At a guess, the PSU has to supply a lot of current for fast charging, so some components will be fairly chunky. Plus if it has to dissipate plenty of heat the heatsink will need a reasonable surface area.

 

[steve_sordy]

I don't know for certain, but it's probably due to the need to step down the voltage from 240V and to charge quickly and without overheating.
The battery may be made of the same stuff as a mobile phone battery, but there is a lot more of them! Maybe you could, try explaining it that way?

 

[knut7]

A valid question!

 

[Gary]

Yeah. Thanks @knut7 my thought entirely!
Thanks @Norange and @steve_sordy but she's not going to fall for those explanations..
She's 9.

hehe


I'm sure I've seen a smaller charger from Lappiere or maybe BMW? that as for a shimano battery and a lot smaller too. could be wrong on that though.

 

[bikerider007]

My laptop charger is bigger than my bosch one???

 

[MattyB]

Key point - these are PSUs, not actually chargers (all the balancing and voltage detection stuff is in the pack). As a result they are likely to be the cheapest available option irrelevant of size that they can source that can deliver sufficient juice, rebadged with the motor manufacturers name. It’s a nice way to eke a little more out of the purchase price as a margin, bit like those nasty hard tyres on entry level mountain bikes.