I'm going to run my Ping 1.0s at 2.5C

[swbluto]

Any bets on how fast they'll decline? The average outside temperature is between 60-80 degrees fahrenheit and it's typically stored in a backpack/pannier like environment during use.

And, yeah, I'm doing it because I have this condition "I'll keep my batteries as long as they serve as the application requirements" and if they don't survive long, tough. Time to get better batteries anyways.

 

[Ypedal]

if you still have a BMS on them, expect early cutoffs due to voltage sag, but this depends on how long they have to give 2.5C.. if it's only 1 or 2 second spikes they may be ok for a while lol

 

[dnmun]

rather than just destroy the ping pack, why not buy another pack able to handle the demands you expect, and sell the ping pack to someone with a lower power demand?

you can use the money from selling the ping pack to buy one of andy's psi packs with gary's BMS. or a headway pack will handle 2.5C too.

 

[pwbset]

I for one would be extremely interested to see stats on the degradation of a Ping pack at higher C rates.

 

[monster]

i would like to find out too. i had to run a pack at 2C today because a wire came unpluged on the other pack. would be nice to know data about this

 

[swbluto]

Thanks for the concern and interest everyone. The reason why I'm not selling them is because it's, let's say, DEFINITELY NOT in its original form and its used value would be correspondingly abhorrently low and I also like to run things to the ground before "upgrading"/"replacing" in order to maximize its long-term useful value to me. I for one would *really* love an a123 pack, but I have the previous belief standing in the way, so I have some interest in getting rid of it sooner. :lol:

As far as testing, I think I should do some controlled tests first and then compare it later on. I have a feeling I'll only put, maybe, 100 cycles on the pack this summer so there probably won't be a lot of detectable decline. Realistically, probably less than 50 cycles given how frequently it seems mechanicals like to break down on me. But if it's going to decline "fast", it'll be noticeable!

I can actually go higher - I mean, I would really like to! But, I have concerns the battery might get piping hot in the back pack. So, perhaps, I should just increase the current rating until it reaches a point where the battery is just too hot. What do you guys think a good temperature limit on the battery should be? Also, what do you think would be a good c-rating to do "testing" at for the sake of adding to public knowledge? It seems the standardized internal resistance of pings is 10x more than a123, but a123s purport to be "30c" but tests suggest they'll be at 180 degrees fahrenheit if you continuously discharge them at that rate! So, it seems that the ping 1.0s would be at 17-180 degrees at 3c continuous but I'll be sure to test that.

View attachment a123graph.JPG

Oops, nevermind. With a123s getting 173 degrees at nearly 20c, It seems at 2.5C, the pings will get plenty hot.

 

[dogman dan]

Heh heh, lots of us would gladly pay you an abhorrently low price for it. It will be fascinating to see how it does. Especially if it takes it. One or two cells that can't would be data too, but if they all handle it , it would be real good news to me. Thanks for doing the test, lots of people will be very interested to see the result. Of course one battery tested this way won't tell all, but it's a start.

Personally I want to run my ping v1 for a few years, and then retire it still functional so it can be a museum piece someday. Kids will see it and go, back in the old days, they had batteries that were covered in duct tape! Wow, look it still works , running those led's.

 

[swbluto]

Well, I do have a few spare cells around here I could hook up for automated testing. So if controlled cell testing is desired, I could possibly do that. I have a feeling that's going to be some ways off, though, as I have to develop the cell tester.

 

[Okassa]

Hum this look very interesting.
Thanks fordoing that test swbluto !! I'm looking forward to the results.