convert a 48 volt battery

[ani19710]

hi all,i was wondering if I could convert my spare 48volt 20ah li-ion battery to 12 volts for running a small or fridge or lights when camping and how would I achieve it ......thanks

 

[dogman dan]

Exactly how would depend on what type of cells you have. But the basics are the same. Separate the pack into 4 sections, each one with 4 groups of cells if it's lifepo4. 3 groups of cells if it's something else that charges to 4v per cell.

Attach larger main wires to each end, then a smaller wire to each cell group for a JST balance wire plug. Now it's wired like RC lipo, and can be charged with RC lipo chargers.

I just did this to my old dead pingbattery. One 12v section croaked, so I cut it up into 12v chunks that now have only half the normal capacity. I can run a tail light bulb as an emergency lamp, power a radio and Ipod, or use any device that runs from a car cigarette lighter. Or I can still run a very low wattage ebike.

 

[ani19710]

thanks dogman,the battery is nearly new and is up for sale,but if it dosent sell im wondering if there is anything I can do to convert the power without splitting for use when I go camping? its a 2.5 ping 20ah 48v....thanks

 

[dogman dan]

You could just open the pack, and solder on a pair of terminals to a 12v section of it.

But DONT DO IT. It would severely unbalance the pack. If you cut the pack up into 4 sections, you could then unplug it from 48v with bms mode, and re plug it in into a 12v 40 ah mode without bms protection. Lotta trouble to go to.

The solution is a DC DC converter, that converts your pings 48v into 12v.

 

[BlackburnPete]

Why not just buy a 48V to 12V DC to DC converter? No need to do anything to the pack. I used one to power an inverter for decorative lighting on my bike.

 

[ani19710]

So if I wanted to run,say a 12v camping fridge can I get a converter already with a plug in cigarette lighter type fitting on it,can anyone point me in the right direction for one,or what other type of connecter would be best

 

[dogman dan]

Once you get a converter, you can easily just add a lighter plug to it's output wires. I'd just look on ebay for the converter.

 

[Alastor]

You could also use a DC/DC module to lower the voltage of your pack to the individual device voltage and keep it as it is witch is better if you ask me.
If you split the pack make sure you will use the devices every day or else it will be a loss of your time and money

P.S.
Splitting the pack and using it on a camping site can be great if there is no electricity.You can put some charge in the pack from a small portable solar panel as well.But you will need individual 4s BMS or whatever configuration you will use to protect your pack.It gets a little complicated but it can work wonders out there

 

[ani19710]

thanks all,going to go for a 48v to 12v converter and keep the battery as is

 

[dnmun]

you can see if the inverters will take the full 58V of the pack and use the inverter directly. or find a cooler that works on 58V DC. or pumps or whatever you need to power. you can go to led lighting and buy the 12V led drivers to power the lighting circuits directly from the battery.

 

[Rassy]

This is a common converter used on scooters to power the lights, etc. It is limited to 10 amps output at 12 volts. This one is priced in euros, but most scooter parts on-line stores will list a similar one. You need to update your profile to show your city, state, country, or whatever.


http://www.zenid.com/converter.htm

Here's one priced in dollars:


http://www.scooterpartscatalog.com/48v-electric-converter-171-19.html