Forum

[John R]

Is it ok to use a standard (non-desulphating ) bike battery charger with a Lithium battery?

[papasmurf]

No, lithium ion batteries require a special charger.

[Scalyback]

There has been a right load of old rubbish written by various sources about this.



Use a normal bike battery charger. These lithium batteries are designed to work with them. Remember, there is no special lithium charging circuit when your bike is running and charging the battery.


Both my RE's have li batteries and a non sulphuring charger will 95% charge a flat battery in about 7 minutes.

[papasmurf]

Scalyback, I was talking to the mechanic who services all of our motorcycles on the subject of Lithium Ion batteries yesterday and his customers who have fitted Lithium Ion batteries and NOT used the correct charger have had all sorts of problems.
It is just one of the reasons I have NOT fitted a lithium ion battery. (That plus the fire risk.)

[Dennis C]

I rather think that someone conversant in electronics is better qualified to give advice than the local mechanic, Scalyback is correct, consider the bike charging system it is far more crude than any modern battery charger.

[papasmurf]

The "local" mechanic has a lot of experience of the problems he ends up sorting out.
The facts are you cannot use a standard Optimate battery charger to charge a lithium ion battery.
I did not want to go to the expense of buying a special battery charger so I did not buy a lithium ion battery.

I was however able to source a maintenance free battery 12v 15amp 220 cca,(Which I did not buy from the mechanic.) that merely required the side connections on it to be used not the top connections which would have fouled the frame.

[Steve T]

Why not phone or email our hosts? They sell them so will be able to answer your concerns.

[jefrs]

The LiFePO4 aka LiFe type of Lithium-Ion battery really needs a charger that does not drop below 14V (like the bike's alternator provides) or it will not achieve full charge.



http://www.powerstream.com/LLLF.htm - quote -

A LiFePO4 battery can be safely overcharged to 4.2 volts per cell, but higher voltages will start to break down the organic electrolytes. Nevertheless, it is common to charge a 12 volt a 4-cell series pack with a lead acid battery charger. The maximum voltage of these chargers, whether AC powered, or using a car's alternator, is 14.4 volts. This works fine, but lead acid chargers will lower their voltage to 13.8 volts for the float charge, and so will usually terminate before the LiFe pack is at 100%.

For this reason a special LiFe charger is required to reliably get to 100% capacity.



The Lithium-Ion really require a two-step charging process, step 1 constant current, step 2 constant voltage.



Four cells of nominal 3.2V gives 12.8V but note full charge voltage is nominal 3.7V per cell hence 14.8V on full charge. Past pro experience by our team found some 12VDC electronic equipment under test did not appreciate this and inconveniently blew up. Light bulbs will draw more current on this voltage and may blow or have their life reduced. The lead-acid has six cells of 2.1V each providing 12.6VDC or less.

[papasmurf]

Put it this way if a lithium ion battery gets subjected to the 22 volt de-sulphating charge from a normal lead acid battery condition charger you will end up with a scrap battery.

[Exile]

I'm with Scaly on this one. If the bike can (and it does!) provide charging, then so will any old charger. Otherwise, we'd all be running about with uncharged and destroyed batteries, or batteries that died within a very short period of time. Not only that, they'd all be described as 'unfit for motorcycles' by the manufacturers...