Charging Ebike Batteries from Car 12volt System

[Terrytraveller]

I have a li-Pol 26volt battery which I would like to charge using the supplied Li-Pol mains battery charger, plugged into an inverter and the inverter wired to the car battery and used whilst on the move.

Has anyone bought an inverter for using with the ebike supplied charger?, did you use the pure sine wave or modified square wave. I wonder what the long term effect will be, if using the cheaper modified square wave. Which inverter was used 300 watt or greater?

The Powacycle Lynx supplied Li-Pol charger is Model GM-240200, input 100v-240vac 50/60hz 1.0 Max (which I take to be 1Amp), output is 29.4v, 2.0A.

Any comments willl be greatly appreciated.

Regards Terry

 

[Chris_Bike]

[QUOTE=Terrytravelle























Most modern chargers are switch mode devices that are very tolerant to a range of voltages and frequencies (making them usable in Europe and the USA). I regularly use power tool chargers off a modified sine wave inverter in an off-grid house.
Chris

 

[Ian]

Hello Terry,

As Chris says most modern chargers are of the switch mode type and are perfectly suitable for use on either type of inverter. The first thing the charger does is to rectify the incoming mains and the actual shape of the AC waveform is unimportant as long as its peak value is within the usually very wide tolerance of the charger.

However, if the charger is of the rarer transformer type it should only be used with a sine wave inverter as damage may be caused to the inverter if it is of the cheaper modified square wave type. Transformer chargers can usually be identified by their relatively large size, heavy weight and narrow input voltage tolerance specification (eg 220-240V as opposed to 100-240V). They are also less likely to have a cooling fan.

I use a modified square wave inverter with a switch mode charger for my bike fairly regularly when away from mains power in my touring caravan, it does the job but it does give the 12V battery a heavy pasting, if used in a car it really should only be used with the engine running. I use an 85Ah leisure battery but in the absence of any external charging can only get about 1.5 full charges of the bike battery out of it. I have also found that the inverter needs to have a rating considerably greater than the charger, in my case the nominally 120W charger overloads a continuously rated 150W inverter, no problems with a fan cooled one rated at 300W though.

 

[Terrytraveller]

Hi Chris,

Thanks very much for your input, I have only a basic understanding of switched mode PSU's, and not really sure what is special about the supplied Li-Pol charger adaptor for the 26volt 10amp Li-pol battery.

I do know that there is some type of voltage controller in the top of the Li-Pol battery box assembly, and the sophisticated Li-Pol charger adaptor must be paired up with the requirements of the battery pack. I understand from my web readings, there is some sort of charge balancing electronic system as well as a thermistor for the heat/charging control in both or either of the two devices.

Now with all that sensitive electronic circuitry about - I really don't know whether I should even risk using a mobile phone near it - let alone some untested inverter .

Any comments will be appreciated, especially if anyone has had experience of charging from an inverter.

Regards Terry

 

[Terrytraveller]

Charging Ebike Battery from Car 12volt System

Hi Ian,

Many thanks for your most comprehensive and detailed reply. I didn't realise the implications that could be drawn from looking at the charger physical size and input AC voltage tolerances. I had a feeling it was a switched mode charger adaptor, as no heavy transformer and input 100-240vac, I feel confident now about buying the cheaper inverter.

Okay on getting 1.5 charges from an 85amp leisure battery, I have two 110 amp Elecsol carbon fibre batteries fitted in the motorhome, charging from the engine and solar panel whilst moving, or camp site supply and/or 85 watt solar panel when sited.

I am not quite sure what load the Li-Pol adapter charger will have on the inverter. The stated input for the charger is 100vac to 240vac at 1.0A max, so as I see it that's 240 watts, I think a 300watt inverter should just about cope, whereas 500/600watt would be better.

Regards Terry

 

[Terrytraveller]

Battery charging from Inverter update

I just bought the Maplins Inverter for £19.99 link Maplin > 300W DC 12 V to AC 240 V Power Invertor their offer goes on until 8th July 2008. The inverter is quiet in operation and the LiPol adaptor switched mode charger charging the LiPol battery is as quiet as when on mains.

All those green people will be glad to know, the Powacycle Lynx LPX is running on sunshine, the power derived from the motorhome solar panel via the leisure batteries.

Anyone remember the Film 'First men in the Moon" everytime the sun dropped below the moons horizon, the beetle like moon men stopped like statues!

With the fuel strikes getting a grip of the country I can see the same thing happening here

 

[Chris_Bike]

I just bought the Maplins Inverter for £19.99 link Maplin > 300W DC 12 V to AC 240 V Power Invertor their offer goes on until 8th July 2008. The inverter is quiet in operation and the LiPol adaptor switched mode charger charging the LiPol battery is as quiet as when on mains.

All those green people will be glad to know, the Powacycle Lynx LPX is running on sunshine, the power derived from the motorhome solar panel via the leisure batteries.

Anyone remember the Film 'First men in the Moon" everytime the sun dropped below the moons horizon, the beetle like moon men stopped like statues!

With the fuel strikes getting a grip of the country I can see the same thing happening here

To those interested in this subject, I've just noticed that Maplins are also selling their 1 kW inverter cheap (£80) till 8 July:
Maplin > 1000W DC 12 V to AC 230 V Invertor
I suspect that Ebay is also full of these. Just depemds how much power you want really.

 

[oldosc]

Have motor home do a bit of travelling
I allso have a Mirror folding dingy, and an electric outboard for it...I charge the outboard (two 50ah bat's )from the leisure (which are two 110 ah gel)As I am camping sauvage most of the time, I had to get a 'STERLING BATTERY CHARGER' which allows one to put 20/40 amps into the leisure when the van is on tick-over (qv) not tooo green but what the hell, what's posterity ever going to do for me.
any one wanting to know more?