Ping balance problems ?

Batteries, Chargers, and Battery Management Systems.
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999zip999   100 GW

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Ping balance problems ?

Post by 999zip999 » Feb 10 2010 5:57pm

I'm trying to get my bike back on the road after I replaced a set of cells on my 48v20ah slim line v2.5. I run it with BMC 600h.s. rear, a crstalyte 36-72v 40amp. controller. The battery was cutting out Ping had me solder the shunts to up the cut off on the BMS. it worked good till I went up a steep hill. O.K. These is where I replaced the cells and Ping sent me a 60amp. BMS. Put it all back together, charged it. It worked it the lights went off then it shut off. The no. 1 cell was 3.71v the rest around 3.82 to 3.84 except 4&5 where 3.88v. counting from the red wire on the BMS.I charged the new cell to 3.8v. It would cut out till I repluged it in a couple of times. Worked find around town. I charged it again a couple of times to help balance. I checked the cells 4&5 where racing between .88-6.25v off the charger. After a couple of charges I checked it and now cells 4&5 were O.K.,But cell 7 is between 3.58-6.25v and cell 8 is .90. If I put back on the charger it will balance to 3.83 to 3.82v off the charger with 61.4v. Then I would start it up No load the lights would start blinking then cut off. the pack is at 14.4v and 57.8v before the BMS. I know This mite be hard to fallow, But computers are new to me,and so is these E.V. bike. Maybe someone could HELP ! Just with the bike for NOW. Forget tring to help with the spelling. THANKS ??????

John in CR   100 GW

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Re: Ping balance problems ?

Post by John in CR » Feb 10 2010 7:05pm

Have you left it on the charger for extended periods, like at least overnight if not 24hrs? The ping chargers go on and off after the initial bulk charge. That is the balancing process, which can take quite a long time if the cells are out of whack.

999zip999   100 GW

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Re: Ping balance problems ?

Post by 999zip999 » Feb 10 2010 7:58pm

Thanks for the reply. I get a little scared about those 2 cells going from .80v to 6.25v no. 4&5, then move to no. 7&8 cells. This is normal in the balancing process ?

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StevenR   100 W

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Re: Ping balance problems ?

Post by StevenR » Feb 10 2010 8:48pm

I have a 48V20aH Ping v3 with the 60A BMS. I am using a 5V Ping aluminum case charger set to go Constant Voltage (CV) at 60.22V.

It may take several hours after the LED's light up for the charging current to drop down to less than 100mA where I consider the battery to be balanced. Cell voltages are 3.75V +/- 0.1V right after the LED's light. Two hours later they are 3.77V +/- 0.02V. They get closer and closer as time goes on, but most of the balancing is done after the first few hours - even after 24 hours there is still about the same +/- but there is often a different high and low cell - the cell voltages are wandering +/- 0.01V.

IMHO: Charge the battery for a long time as often as possible. If it used every third day or more, never take it off the charger.

The light blinking behavior is normal and I consider it a good sign. Mine will stay lit for an hour or so then they will start to blink. The blinking can go on for hours with groups of cells lighting up solid for a few seconds on occasion. I can watch it for hours, but then again, I am easily amused.

I think I saw the "racing" you describe with the old BMS on a failing battery with a charger set around 61.2V but on that battery several cells never came up to 3.8V - they stayed at 3.3 until they went to 0. I am a bit concerned your charger voltage is too high but usually a little high is better than low - too low (less than 58.5V) and it doesn't balance correctly and your battery dies. If they stabilize around 3.8 with the charger at CV you should be good. If your charger has a voltage pot you can probably tweak it down a bit and see if it goes away. Sometimes there is a bonus current pot you can tweak up to get 110% out of a charger - I got a Soneil up to almost 4A that way.

(CAVEAT: The calibration of the VOM is out of date but it seems pretty close; the +/- is probably right as I can repeat the measurement +/- 0.001 but the absolute value of the voltages is questionable to some degee).

These values were taken at about 1000 miles, 120 cycles. I will try to do another run as I am at about 2500 miles...
Bianchi Alante MTB with C'lyte 5303 Front Hub Motor / Motobecane hardtail MTB with C'lyte 5303 Rear Hub Motor
CT48V35A Controller / method monster 100A100V controller
Schwalbe 26"x2.3" Big Apples / 26" Schwalbe Ice Spiker Pros
Ping v3 48V20aH with 60A v2.5 BMS / Headway 48V10aH BMS used to balance, bypassed on discharge
Pick one from each row above

John in CR   100 GW

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Re: Ping balance problems ?

Post by John in CR » Feb 10 2010 8:56pm

999zip999 wrote:Thanks for the reply. I get a little scared about those 2 cells going from .80v to 6.25v no. 4&5, then move to no. 7&8 cells. This is normal in the balancing process ?
Both of those voltage extremes sound incorrect, because that parallel group of cells is most likely already dead. Let the thing balance charge properly until the charger stops going off and on. Then take a measurement without the BMS even plugged to the pack, which should give you a meaningful status of your pack's condition.

If there's something wrong, it sounds like you've been messing with it quite a bit too much. Do you go taking your microwave apart and messing with the electronic guts? EV's should be just plug and play unless you DIY. If you want to monkey around with the electronics as a learning experience, that's fine, but consider that you do so at your own risk, and your initial post was unclear regarding what you actually did. I'm an electronics moron, so don't waste your time asking me. My ping pack didn't come with instructions, so the balance charge process is something not readily obvious to someone new, so I posted.

Velocipede   1 W

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Re: Ping balance problems ?

Post by Velocipede » Feb 11 2010 12:25am

The ping v2.5 20Ah is really made for a maximum of 20A continuous.
If you pull 40A and even more regularly, you should know that you reduce your pack life by doing so.

I read your post twice and don't get your voltage readings. A cell can not got to 6V and over. If you do measure cells under 2V, they are dead. You mention replacing cells. Are you sure about the way it was done?

dnmun   100 GW

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Re: Ping balance problems ?

Post by dnmun » Feb 11 2010 12:43am

i kinda agree you don't seem to recognize how serious is the impact of the low and high voltages. it is really hard to figure what has happened from your comments. the BMS should cut off the charge if any cell gets to 3.9V, and it should not deliver any current if any cell is at .8V. i know ping makes and sells quality equipment so i don't believe any of it was defective when you received it and i fear your inexperience has misled you into thinking there was something wrong without knowing what it is so you may not have needed to replace those cells either. maybe your problems started then.

999zip999   100 GW

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Re: Ping balance problems ?

Post by 999zip999 » Feb 11 2010 2:35am

Here what happen the was cutting out going up hills Ping told me to solder the shunts to bring up the cutoff. The battery had blown a cell ( like a ballon ). So Ping sent me a set of cells and he told me to install a 60amp. BMS. After doing so and charging the 1 cell was low 3.4v, I brought the up 3.8v. still was having shut down problems. The cells 4&5 from the pos. end the end that had blown, had a reading of .90-6.44v up and down fast it was off the charger over night. Then it moved over to cells doing the thing after 12hrs. on the charger. O.K. Now I went down to check, it's 61.4v, and 3.7 to 3.8v off the charger. It drops off quickly to 59.4v I plugged it in to leave on for 12 more hours then check it. No I did not just cut it open to see whats inside. I do need to get a C.A. to turn down the amps. but what's with Ping selling me a 60amp. BMS ? I told the 40a con. was the best for my set up and would be troble free. I'm just learn a hard leason. But the vendor learn from my money and my time.

999zip999   100 GW

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Re: Ping balance problems ?

Post by 999zip999 » Feb 11 2010 2:44am

Yes I'm measuring the cells at the BMS where the leads wires go into a white plastic block. Tomorrow I will test the cells unpluded from the bms through the white block unpluged. After 16 hrs. Hay thanks for your help.

999zip999   100 GW

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Re: Ping balance problems ?

Post by 999zip999 » Feb 12 2010 12:00am

O.k. I think I corner the cat. I have a 48v 20ah split pack or slim pack. It has a 8 wire plug for the BMS for the front pack, I had noticed the pins were low in the plug put them back together. That my be the 4 & 5 cell measure of .09-6.25, I guess. Still had to charge up the new set of cell from 3.6v O.K. to 3.8v. In the process the wire between 7 & 8 at the 16 wire BMS was broke inside the insultion, I found this when I unpluged the 16 wire plug from the BMS to check the voltage. THANKS JohnCR, I wouldn't have found it If you didn't suggest to check it unpluged. I used it for 3-4 miles, now it's plugged to charge for 14hrs. StevenR my charger has 61.4v that's O.K. ? When I get the money I will get a C.A. My vendor now sales the BMC 600 with the 25amp. controller from BMC. Camdu the guy how runs BMC the (800) number on the wheel did not like the 40amp. controller for BMC motor. So next step is to turn it down.Thanks Velocipede. Hope this is it guys THANKS !
'

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monster   100 kW

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Re: Ping balance problems ?

Post by monster » Feb 12 2010 5:54am

if you still have problems you could considder sending it back to ping, or someone with more experience.

999zip999   100 GW

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Re: Ping balance problems ?

Post by 999zip999 » Feb 14 2010 2:41am

Hay Hay well it may be Golden three rides getting better evertime. The problem I thank was the added block for the 8 wires between the two batteries at the white block connnection. The outter instlation look good but was no good it would at times test at 3.8v till unplug from the BMS and checked from the wite plkug before the BMS. GOOD JOB for all the help !!!!!!!!!!!!!! but only half MY questions were answered FORWARD I WILL GO !!!!!!!!!

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