I think I finally killed my PING v1

[grimbasement]

Subject says it all I'm pretty sure my 36 V 20 Ah Ping finally died. I recently moved up the hill so as to have a 500 ft vertical avg climb of 4% a for a little over a mile. The battery is no longer charging past 37 v. and I haven't check balancing as I lost my multimeter in the move bit that's not a biggie I'll go buy a new one, but I'm guessing I need something with a higher c-rate. Could someone post pings instructions for balancing with a single 3.5 v cel charger... I've done it before but it was over 3 years ago... I remember hooking the aligator clips to safety pins in each of the spot on the harness that plug into the BMS but can't remember the exact instructions to balance.


Controller I have is a 35 A 12 FET BMC modded controller and a v2 BMC with the crappy thin phase wires so it's not a really robust system, but it can climb decently, if done carefully (which I didn't do for a couple of days which is when I hosed the Ping). Thinking of picking up a A123 pack from cel-man or wanted to see some other battery options with a higher c-rate. and see if I can salvage the ping for running around the flat parts of town.

But the Ping served me very well for 3 years and about 3500 miles and who knows with some of the ingenuity around here maybe I can still save it, but regardless I need something beefier, but not more that 48 V and minimum 10 Ah range...

Over all commute to work is only 3 miles each way but do like having some range for longer weekend jaunts which is why I loved my 20 Ah Ping.

So spend my money for me... any ideas on both repairing the ping and battery upgrade options?

 

[dogman dan]

Not so many miles, but three years from the ol ping aint bad. You may have seen it that mine died too, after I stupidly left a bike turned on for about a month.

Find or buy a multimeter for starters. If it's just way out of balance, maybe a new bms could fix it. Mine died because my bms had gone bad, but the way I used the bike I never knew it. The V1 bms makes enough heat to eventually cook itself. The new bms is much better.

A cellman 9-10 ah pack sounds perfect for your use pattern. Maybe you could rebuild the ping into a good 10 ah pack, and run it paralell with the cellman pack. But a lot of work to rebuild a ping. Too much soldering for me.

Your short ride on the weekdays sure sounds like a lipo battery would work great for you too. 14s 5 ah would rock.

 

[neptronix]

Remember kids.. ping is rated to last 1000's of cycles.... at under 1C draw ( lol, yeah as if anyone really runs their battery at that low rate.. )

12S lipo would rock your world, it would perform as good or better than a 48v ping until near the end of the charge when it poops out

Doing surgery on a ping is like dealing with a lipo but notably worse. Not fun. Rip it apart, see what you get to deal with and let us know if you really want to work on it or not, lol..

 

[grimbasement]

Dogman, I am actually hoping that it is just the BMS. For some reason I decide WOT was a good idea based on something I had read her on ES so the battery only lasted a couple of days and never it charged above 37 V after those WOT climbs... stupid. Previously on climbs I had always kept the throttle real low and just peddled harder. On the positive side the motor and controller performed just fine barely getting hot.

So can either of you give me a quick refresher on balancing the cels in the ping pack?

 

[dogman dan]

Like I said, get or find the multimeter and let's see if it is out of balance. Theoretically, that thing should have handled 20 amps since it was a 20 ah pack. A v2 pack should have been more able to handle 35 amps. So your controller was big for a V1. No telling how much both of our problems were aggravated by calender time, but I never expected calendar life much past 5 years.

Once you identify which balance leads are + and- for the cell that is very low, attach some way or other a 4v cell phone power supply. Then watch the thing charge very carefully, and stop when it is near the same voltage as the other cells, after you remove the charger current. If a cell group charges but won't hold a charge like the others do, there's your problem. Chances are good you've murdered a cell or two, and some of the cell groups are now only 10-15 ah capacity.

Wot might have been best for the motor and controller, but not for a battery that is near the max discharge rate at wot.

Regarding hill climb strategy, assuming the battery can do it charge short steep hills wot and take em mostly on momentum. Back off on extremely long hills till you are running a wattage the motor can tolerate for long periods, like 800w or so, then pedal your ass off to get speed back up to 15 mph. Moderately long hills, like 1-2 miles can be taken wot, provided the grade is not so steep the motor slows below 15 mph. The critical mph to stay above varies by motor winding, but 15 mph works for typical kit motors.

 

[grimbasement]

good news... I think the battery might be fine and the BMS is the problem. I checked the voltages of the individual Cels and all but one were balanced for a depleted pack... all cels read 3.1 volts except for one that registered 2.95. I have a order in now with Ping for one of the newer BMS...Crossing fingers. I'm waiting for a reply from cel-man because I'm still going to purchase another battery. But thanks for the help.

 

[dnmun]

you do not know if the pack is balanced until you can measure the capacity. cell voltage does not tell you if it is balanced. balanced is when all cells have the same amount of charge stored. you still have to bench test the pack to establish which cell is losing capacity. usually it is a broken tab, figure out which cell is low by discharging the fully charged (3.65V min on each cell) pack into a load, like a heater or lights, and measure the discharge through a watt meter or ammeter until the first cell hits 2.1V. that is the capacity of the pack, that will show you where to look for the broken tabs.

instead of the BMS which is ok, you should wait and order new pouches from ping when you know which one is bad.

 

[auraslip]

cell voltage does not tell you if it is balanced. balanced is when all cells have the same amount of charge stored. you still have to bench test the pack to establish which cell is losing capacity.

Well, that is technically true, but a low tech way to figure it out is to check the cells at LVC. I have 4 bad cell groups (that I damaged from overcharging to 4.1v) and as soon as pack voltage drops noticeably, I can see those 4 damaged cells have dropped to 3v even though the rest of the pack is only at 50% SOC. So if you want to discharge your pack a bit, and then check with a multimeter you can easily find obviously damaged cells. Most likely, the cells are close enough in capacity that it would be hard to do it this way.

As most people have noticed, the cells themselves are quite hardy; it's almost always the BMS at fault (or wiring)

Could someone post pings instructions for balancing with a single 3.5 v cel charger

yes please!

I still haven't figured out what I'm going to do with my damaged 16s pack. It's still in use (almost 10,000 miles!), but eventually I'm going to have to either make it a 12s pack or replace the cells. I was thinking of putting the 4 damaged cell groups in parallel with the good cells for a 12s25ah pack. Or maybe just make a 4s4p 12v pack out of them for.... I dunno.

 

[dnmun]

i disagree, i have found that the most common problem is from operator error. charging cells without a BMS or discharging without a BMS until over discharged. the ping BMS is simple and rugged, and the failures are from the overheating of the output FETs causing them to burn up without proper cooling.

you can balance the individual cells by connecting them all in parallel and charging the lot to 3.65V.

almost all the problems i have seen with the ping packs is from broken tabs that allow one cell to drop in capacity by the amount of the disconnected pouch. it is an easy repair, once replaced the pack should still provide service.

i find most people just use the hit or miss type of analysis when conducting repairs on their pack, and make fatal mistakes in the misguided presumption they know more than they do about what is balanced and what is not. very few actually test the capacity of the pack or measure cell voltages while charging as the first analytic step in fixing their pack.

essentially the same as replacing a tire when the motor has a blown rod. then they drive it more until it is ruined (without the BMS), and bitch about ping, demanding he send them a free BMS to replace the 'bad' one.

 

[grimbasement]

Attached is the image that Ping sent for testing the individual cels.

And Pings instructions:

Measure voltages from v1 to v12 based on attached diagram. The red line represent red probe of the meter. The black lines represent black probe. If any of the voltages is lower, just charge it up with a single cell charger or dc power supply at 3.8v 2a or lower current. You can just charge it through the two pins where you measure its voltage.

Ping really is a first class vendor seriously who else would provide support for a product bought way back in 2007?

I will charge all the individual cels tonight I"m wondering of the one cel that is showing as 2.95 is keeping the BMS from charging? Like I said, I'm hopeful that this can be salvaged. I'm even optimistic seeing that all the cels at LVC are really close to being balanced.

 

[auraslip]

I'm not disagreeing with you. In fact I agree; ping has a good, rugged product. The cells themselves are the strong part. The wiring and the bms is usually where things go wrong. And this leads people to assume the battery is "bad." But it's always just some minor thing. It's like saying, "The motor in this car has gone bad!" When really, it's just the distributor or some small, easy to repair part. To continue this analogy, I'd say that the actual motor in the ping is a good quality product, but perhaps the accessories could be a bit more durable. When you have a product that is supposed to last ten years (2000 cycles), you'd think the bits and pieces to keep on ticking too. Or maybe I'm just being a bit demanding on a battery pack at that price level? I'm sure a BMS and wiring harness that would last ten trouble free years would be a lot, lot more. Some times an engine will run for 200,000 miles, but the starter kicks it at 50,000.

And as always, lets not forget that there are probably more people using happily ping on this forum than any of the other options. So no one should ever think that just because there are more issues with ping posted, that it's any less reliable than the other options.

 

[E-bike4life]

:wink:

I will charge all the individual cels tonight I"m wondering of the one cel that is showing as 2.95 is keeping the BMS from charging? Like I said, I'm hopeful that this can be salvaged. I'm even optimistic seeing that all the cels at LVC are really close to being balanced.

If one of the cell's is at 2.95, then yes, the BMS should stop the battery from charging. Do exactly as you are planning and charge up each low cell to 3.6v through the balance wires (2 amps or less). Sounds like you may still have some life left in that battery. :wink:

 

[E-bike4life]

I was thinking of putting the 4 damaged cell groups in parallel with the good cells for a 12s25ah pack. Or maybe just make a 4s4p 12v pack out of them for.... I dunno.

Go with the latter idea (4s4p) for noncritical application. Batteries tend to share current when paralled together. The bad cell would bring the good cells down to its level of charge (which will always drop faster than the good cells)

 

[miniebiker]

I'm not disagreeing with you. In fact I agree; ping has a good, rugged product. The cells themselves are the strong part. The wiring and the bms is usually where things go wrong. And this leads people to assume the battery is "bad." But it's always just some minor thing. It's like saying, "The motor in this car has gone bad!" When really, it's just the distributor or some small, easy to repair part. To continue this analogy, I'd say that the actual motor in the ping is a good quality product, but perhaps the accessories could be a bit more durable. When you have a product that is supposed to last ten years (2000 cycles), you'd think the bits and pieces to keep on ticking too. Or maybe I'm just being a bit demanding on a battery pack at that price level? I'm sure a BMS and wiring harness that would last ten trouble free years would be a lot, lot more. Some times an engine will run for 200,000 miles, but the starter kicks it at 50,000.

And as always, lets not forget that there are probably more people using happily ping on this forum than any of the other options. So no one should ever think that just because there are more issues with ping posted, that it's any less reliable than the other options.

Right ? I am still using NiMH Texaco packs over 10 years old. I got them real cheap because they would not charge because the temp sensors in both packs were bad.

 

[dnmun]

2.95V will not stop the BMS from charging. it does not work like that.

the charging FET will always be turned on when all the cells are below 3.9V. if any of the cells climbs above 3.9V then the opto isolator for that channel turns off and the charging FET loses the gate voltage that keeps it turned on.

check gate voltage on the charging FET.

 

[grimbasement]

Thought I'd take a minute to update this thread... I ordered a replacement BMS from Ping opened up the duct tape and replaced the BMS connector wires and admired what a cool setup the Ping pack really is, quite the design IMO. So for the last few days I've been charging and bleeding off with short around the block rides (but mostly charging) and I finally have all the lights on on the new BMS so they all turn on and all are balanced at 3.5/3.6 V and 42 something volts FOC which is what the charger puts out . But the performance just isn't there, lots of sag like dropping down to 35V and 34 V under moderate loads. I'm suspecting I have a runt cel(s). I might try my other charger that puts out 45 v

Still though I beat the hell out of the Ping v 1 over the last month or so after moving up the hill, and am very pleased with what I got out of it, which is why I ordered another one. I can see A123 in my future though. So with all that said I'm going to keep working on the balancing of the pack and keep and eye on it any hopefully nurse it along until the other pack comes, but it's just not doing what it has in the past.

On the good side I pulled the trigger and got a 48V 20 AH Ping on order on the slow boat from China so hopefully the new pack with the slightly higher C rate and more volts will give me what I need to climb up the 450 ft elevation gain over the Ping v1 36v.

 

[auraslip]

What sort of voltage sag were you experiencing in the past?

Btw, If your interested, I'm sure you could find someone to take the 36v ping off your hands for the purpose of rebuilding/testing.

 

[grimbasement]

Usually it wouldn't drop much below 36V but I have to remember that most of my riding then was on the flats of the valley. There is a slight uphill grade all in all but one direction so I need to remember that the bike won't perform the same way. I haven't tried the 8% uphill climb yet but I'm thinking this might still be a decent pack for flats on long touring rides and as a backup if I want to carry 35 lbs and 40 Ah in batteries which is a possibility on a cargo bike. The bike is primarily a commuting tool. But this Ping seems to be living another day... It's not dead yet apparently.

 

[dogman dan]

Good to hear you saved it. Wish I'd noticed the problem I had in time to save my V1. By the time I got done bieng sick, and went to ride, that thig was at 3v for the whole pack. Puffed as hell.

We need to start a ping v1 last man club.

 

[999zip999]

A123 cellman sounds like a good pack if you go down that raod let us know how you like it.

 

[grimbasement]

I sent Cellman an email about 3 weeks ago about buying one of his packs... never heard back from him. I need to do some searching on the forum to see what the concensus is about the BMSbattery A123 cels and BMSs and build my own pack with the 38140S.