Charger Help

[NRG]

Hi, I'm looking for some advice / guidance on a 'travel' charger please.

One of my bikes is a Kalkhoff Panasonic drive bike but the 'base station' charger is too bulky to take with me touring. Kalkhoff sell a travel version of the charger but is costs an eye watering $200. So I'm trying to find out if I could use something else or assemble a small neat pocket size (or so) charger.

The internals of the 'base station' charger are below. To my untrained eye this looks like a switched mode power supply, there seems to be no BMS or protection circuitry in there. Output is 1.8Amp and 29.3v.

I use modified Meanwell supplies for my DIY build bike to charge Turnigy RC packs but even the Meanwell's are bulky to transport around.

Any ideas or suggestions please

Many thanks.

 

[dogman dan]

What's the battery chemistry? I can't keep up with all of them. Sounds like a 24v system, could he use a 24v sla charger? I'd think so if the battery has a bms.

 

[NRG]

Hi Dogman,

Lithium-ion I think, listed as a 26v system. I was looking at these buck converter modules last night but don't think they will be suitable....

http://cgi.ebay.co.uk/LM2596-DC-DC-Step-Down-Adjustable-Power-Supply-Module-Z_W0QQitemZ160485414577QQcategoryZ4661QQcmdZViewItemQQ_trksidZp5197.m7QQ_trkparmsZalgo%3DLVI%26itu%3DUCI%26otn%3D4%26po%3DLVI%26ps%3D63%26clkid%3D5336172122357520112

What I need is a small adjustable 2amp CC/CV supply like the Meanwells.......

 

[heathyoung]

Why not use one of the small SLA chargers for chinese scooters etc off ebay - 29V would be for a 24V lithium system right? A 24V SLA charger (would be charging at around 14.4 - 15v per battery = 28.8 - 30V - would be pretty damn close to the mark and cheap too!

 

[jondoh]

if you specify the voltage and chemistry to bmsbattery, they'll build a charger for you. Problem is that there won't be a connector. You'll have to solder the appropriate connector.

 

[NRG]

Thanks for the ideas.

I've located this SLA charger that seems it could work:

http://cpc.farnell.com/1/1/47554-charger-24v-2a-lead-acid-ac0224a-ideal-power.html

or I could try and modify this 60w 24v 'Meanwell' SMP ......

http://uk.farnell.com/mean-well/s60-24/psu-enclosed-24v-2-5a/dp/1209669

Does anybody have any thoughts as to which would be the best approach?

Many thanks!

 

[NRG]

Attached is the charge profile for the SLA charger, the blurb lists the voltage as 27.4 and 29.2v

If the 29.2v is the upper DC voltage then its just about on the money, however, I'm unsure if Li-ion can be charged with an SLA charger. The battery also houses a BMS I should add....