Alternative to Ping Charger - Pedelec Forums

chrisrenwick · #1 (**permalink**) 26th August 2008, 09:11

Hi I was wondering if anyone new of an alternative to ping's 36v LifePO4 battery charger?

Jeremy · #2 (**permalink**) 27th August 2008, 22:01

I don't know of one, but they come free with the battery plus Ping can supply spares for just a few pounds each, so it hardly seems worth the bother of trying to find an alternative.

I know that other have bought spare chargers from him at a reasonable price, so your best bet might be to just send him an email and ask.

I doubt the charger circuitry is that complex, so it might be possible to build an alternative. Mine runs at a constant current of a couple of amps until the BMS starts to limit, then it switches to constant voltage and just allows tyhe current to trickle down to a very low level. As the BMS balancing process starts, the charger will occasionally trip back into constant current mode for a few minutes, before reverting to constant voltage.

It may be that a straightforward current limited DC supply set to the right end voltage would be as good.

Jeremy

chrisrenwick · #3 (**permalink**) 28th August 2008, 17:32

I have already had two of ping's chargers had both suffer from the same problem (see my thread entitled Ping Battery Charger). Can anyone give me any idea where I can locate an alternative. Many thanks,

Chris

Jeremy · #4 (**permalink**) 28th August 2008, 18:33

Chris,

Sorry, I'd not seen the Ping charger thread before you pointed it out.
As you can't get either charger to work, I suspect some other problem, as, although possible, it seems unlikely that both chargers were "dead on arrival". The problem might be a fault in the battery BMS, if the BMS is open circuit then the charger will just show both LEDs all the time and won't charge.

I would be more than happy to have a look at one of your duff chargers to test it, see what's wrong with it and whether it can be easily repaired. My own 36V Ping battery and charger works flawlessly, so I could compare the two circuits to find out where the problem is and test the charger out on my own 36V Ping pack for you.

I'm near Salisbury.

Jeremy

chrisrenwick · #5 (**permalink**) 29th August 2008, 09:01

thankyou for your kind offer but I have already disected the chargers and disposed of them

john · #6 (**permalink**) 29th August 2008, 10:17

A Yesa charger should do the job

LiFePO4 Battery,LiFePO4, the best choice to replace Lead acid battery!

Jeremy · #7 (**permalink**) 29th August 2008, 19:22

John,
That Yesa charger looks pretty similar to the one I have that came with my Ping pack,so may have a same sort of high failure rate.

Chris,
What did you find to be the cause of the failures in the two defective chargers you dissected? It'd be very useful to know in case mine fails at some future date.

Jeremy

chrisrenwick · #8 (**permalink**) 29th August 2008, 21:56

Both had no current in the output -I tested with volt/amp meter

Jeremy · #9 (**permalink**) 29th August 2008, 23:37

Thank for that information Chris.

Out of interest, did you do the output voltage check with the pack connected? I have a feeling (but would need to check with my own set up) that this charger needs to see the battery voltage on the output before it will turn on. Testing it with no battery connected may well result in getting a zero volts indication.

I've got another charger (albeit a sealed lead acid one) that I know for sure behaves like this, because I also thought it was dead.

I'll check my set-up tomorrow and let you know how mine behaves.

Jeremy

Blew it · #10 (**permalink**) 30th August 2008, 01:50

Hi guys,

Hope you don't mind my sticking my nose in, I have two nine month old Ping batteries, One 24 volt 15 a/h and a 36 volt 10 a/h.

When preparing these batteries for use, and after soldering the XLR plugs to the charger output leads, I remember that I checked the polarity was correct.

These checks were carried out WITHOUT the charger connected to the batteries. The open voltage measured at the charger lead XLR pins were: 39.9 volts for the 36 volt charger. 28.9 volts for the 24 volt charger. It may well be Jeremy, that the chargers in fact do not need to see a voltage as you thought. I'm not very good with electronics, so please don't be offended if I'm wrong.

The chargers are a bit suspect regarding quality, but in fairness to Li Ping, I would be inclined not to be too critical of them. After all, they are £20 chargers.

I remember when my 24 volt pack arrived, as soon as I unpacked the charger, I could hear something rattling about inside. This proved to be a reverse current diode which had "fallen off" the PCB. With this component re-soldered to the board, the charger worked fine, except, it sometimes needs a "barney flinstone" tap to persuade the cooling fan to start.

I hope this may help in some small way.

Regards

Bob