jha07 said:Has anyone had any difficulties getting their ping pack balanced? I recently noticed that my range seemed to be a bit less than when the pack was new. So I decided to check the voltages of each cell. I found that I have one cell that is low (3.3v) while all the others are >3.7v. I've tried letting the pack charge for long periods, up to 3 days, to see if it would balance. No luck yet. I emailed ping about this, and he suggested charging the low cell separately. I am reluctent to do this because I really don't want to be doing this on a regular basis. I remember when the pack was new, I had all the cells balanced, so somehow, the pack went from being balanced to not.
I don't have a meter, but I do have a 20A controller, so I'm drawing less than 20A. From my calculations, I draw about 8-10A average. Just as a test, I ran with a 15A fuse and it lasted for a week before it blew.dogman said:Do you have any idea how many amps you usualy pull from the battery? Just trying to get an idea if there is any correlation between people with big motors and high discharge rates and loss of range.
nomad85 said:jha07 said:Has anyone had any difficulties getting their ping pack balanced? I recently noticed that my range seemed to be a bit less than when the pack was new. So I decided to check the voltages of each cell. I found that I have one cell that is low (3.3v) while all the others are >3.7v. I've tried letting the pack charge for long periods, up to 3 days, to see if it would balance. No luck yet. I emailed ping about this, and he suggested charging the low cell separately. I am reluctent to do this because I really don't want to be doing this on a regular basis. I remember when the pack was new, I had all the cells balanced, so somehow, the pack went from being balanced to not.
I had the exact same problem. I got a single cell charger from volt freaks, and charged the cell through the bms wires. The cell reverted to 3.35 volts after the next charge though. Maybe you will have better luck. In any case contact ping, he is helping me solve the issue. Is your battery a V1 or V2, mine is a V1.
Don Harmon said:I have a similar question on Ping Packs ? Is there anyone out there who has pulled 4C (40 Amps) on a continuous basis in their testing? If so how many deep discharge cycles has been done ever on a Ping Pack ? The answer may have been posted on this forum somewhere - but given the volume of Ping related posts I can't find anything close to refer to.
Thanks,
Don Harmon![]()
ZapPat said:Don Harmon said:I have a similar question on Ping Packs ? Is there anyone out there who has pulled 4C (40 Amps) on a continuous basis in their testing? If so how many deep discharge cycles has been done ever on a Ping Pack ? The answer may have been posted on this forum somewhere - but given the volume of Ping related posts I can't find anything close to refer to.
Thanks,
Don Harmon![]()
Don,
As you can see from this thread's previous page of postings, I have tested a Ping battery at 1C constant only so far, and have not had time to do a 2C test so far. As for 4C testing, ping does not rate his cells at 4C constant, only 2C constant with 4C peak. And of course we never really know what "peak" means - how long a peak??
I understand. How many deep discharge cycles have you done @ 2C constant ? Has anyone ever done 300 deep discharge cycles on one of these packs ?
Best,
Don Harmon![]()
I tried to get Ping to send me a couple extra cells to do potentialy destructive/degrading tests on when I ordered my 48V20Ah pack, but he didn't follow through for reasons unkown to me (maybe economic or other?). Because of this I won't be doing any tests over 2C constant since it is my own pack I'm testing and don't want to scap it. It also makes it impossible for me to do long term deep-discharge tests at different C rates to see how the cells would cope over time. Too bad... Maybe I'll ask him again sometime now that he has his own website.
geoff57 said:Don are you getting up to your old tricks again.
you know full well what pings cells are able to do.
1c to 1.5c they will give ideal performance with no great drop in voltage.
2c this is the safe limit IMO for ping cells for continuous discharge.
3c to 4c for a burst period of 15 seconds or so should not dammage the cells, this is an opinion and the BMS will not let you test it anyway.
pings best selling pack is probably the 48v 20ah this has the following characteristics
the 4c you were asking for would be 80a, pings BMS cuts at 40 max on that pack
if you bypas the BMS and use a seperate LVC board say from Gary you should be able to draw 80amps out of the pack, it would dammage it
lessen the number of charges alot but you don't care this is a test. now we come to the other side of the equation, what motor can take 80amps at 48volts and what reasonably priced controller can handle 80 amps without blowing its lid.
further more if you can answer those questions do you really think an ebiker would want to ride an ebike that went that fast.
No tricks at all - just trying to better understand the real needs of e-bikers - so thanks for the post. It clears up a lot of things for me.
Best,
Don Harmon![]()
I have said before and will say again your batteries are great but they are overkill for any ebiker that wants to replace their car with an ebike to get to work and has chosen one of pings 20ah packs you can't compeat on price for range only power and people who buy ping know that power is not the best but for range ping is hard to beat.
geoff