Correct charger for 24V E-Bike Battery

[Wallace4793]

Hi,

I have a Chadwick and Taylor E-Bike, inherited with no charger for the battery. Does anyone know what battery charger I need. It is a 24V 8.8mah battery and looks to have a standard 2.1/5.5 barrel connector.



John

[Jdsk]

The image isn’t showing for me.

Jonathan

[Audax67]

Hi,

I have a Chadwick and Taylor E-Bike, inherited with no charger for the battery. Does anyone know what battery charger I need. It is a 24V 8.8mah battery and looks to have a standard 2.1/5.5 barrel connector.



John

I'd guess 8.8 Ah - you wouldn't get far with 8.8 milliamp-hours. Your barrel connector is probably a coax connector. You'd need to know the polarity before hunting for a charger, though. Now while I don't know much about it I have read that my own charger, which is for a 36v battery, charges at 41v, so it would seem logical that you'd need a one that'd turn out ~28v. Mine runs at 2 amps: yours could be similar.

I had a look at Chadwick and Taylor. Sorry to say it, but from the look of their site I wouldn't buy anything from them. Have you tried contacting them?

[rjb]

Quick search on Amazon for a 24v electric bike charger lists thousands.
Looks like the charge voltage is 29.4V, and the round pin connector is pretty common. Charging current is listed at 2 or 4 amps. Polarity wise the centre pin is likely to be positive but you will need to check your battery and the charger before purchase.

[bikes4two]

Just for other readers,

• the ebike battery voltage quoted in sales blurb is the nominal voltage of the battery, e.g. 24v, 36v, 48v

• Lithium cells, normally 18650 cells, each have a nominal voltage of 3.6v but when fully charge are 4.2v per cell

• so for a battery pack of "24v" there will be 7 cells in series (and a number of cells in parallel that determine the overall Amp hours of the pack) so a charger of 7 x 42v - 29.4v is required

• similarly for a 36v pack, there are 10 cells in series so the charger voltage is 10 x 4.2v = 42v

• likewise a 48v pack is 13 cells with a corresponding charger giving 13 x 4.2v = 54.6v

• As for the charger jack plug, the convention is for the centre pin to be positive - I'd bet my best chain removal tool on that being the case for every charger plug including laptops and the like.

And as a bonus for the curious, a 18650 battery is so called because its diameter is 18mm with a length of 65mm (and they weigh approx 42gm-45gm each)

I hope that helps?

[rjb]

Whilst the current convention is for plugs to have the centre pin Positive it's not always been this way. I've an old Sony radio and Casio keyboard which have Negative centre pins.