# CALB CA / A123 / Sinopoly testing, what would you like to see?



## muffildy (Oct 11, 2011)

id love to see how well the cells perform under a simulated stop/go cycle.
for the 100 amp cells for example, draw 750 amps for 20 seconds, then 250 amps for 40 seconds then regen for 10 seconds, repeat as much as possible without the cell overheating or going too dead.


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## mora (Nov 11, 2009)

Powerlab monitoring cell voltage while discharging using external load. Discharge down to manufacturers recommended voltage at 1C for "true" capacity. Don't do CC/CV discharge.

Charge cell to its recommended max. charge voltage. Discharge at 1C for about a minute (top charge voltage will fall off) and increase discharge rate to 2C. Exact rates are not necessary, you should just note amps and volts carefully. Note voltage drop and calculate internal resistance. Do this at 99%, 50% and 20% SOC.

Extra: compare measured IR with Powerlab's own IR measurement which is done during charge.


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## rwaudio (May 22, 2008)

muffildy said:


> id love to see how well the cells perform under a simulated stop/go cycle.
> for the 100 amp cells for example, draw 750 amps for 20 seconds, then 250 amps for 40 seconds then regen for 10 seconds, repeat as much as possible without the cell overheating or going too dead.


In the car I can't draw 750 for 20 seconds, I'd be speeding or harm the car or myself (my 0-60 is probably around 5 seconds) there are some hills I could probably push it to to 10 or 12 seconds near full load. Again 250A for very long unless I can find a good hill will be difficult. My car has a DC system so no regen. I can hit the desired current levels but I'm guessing they would only be 5 - 10 seconds at a time. This isn't long term testing, it's meant to be comparative testing since I will have a CALB CA and Sinopoly on hand at the same time. IE one sags to 2.90 at 500A and the other to 2.75 and repeat for different currents and states of charge.



mora said:


> Powerlab monitoring cell voltage while discharging using external load. Discharge down to manufacturers recommended voltage at 1C for "true" capacity. Don't do CC/CV discharge.
> 
> Charge cell to its recommended max. charge voltage. Discharge at 1C for about a minute (top charge voltage will fall off) and increase discharge rate to 2C. Exact rates are not necessary, you should just note amps and volts carefully. Note voltage drop and calculate internal resistance. Do this at 99%, 50% and 20% SOC.
> 
> Extra: compare measured IR with Powerlab's own IR measurement which is done during charge.


I might be able to rig up a load that was close to 1C however it would be resistive and not constant current unfortunately. I do like the idea of calculating the IR vs just taking the value out of the PL6 and doing it at different SOC, I will try and work that into my testing.

I may not have both cells for that long but I'd like to get in some useful testing to see how the Sinopoloy's really do compare to CALB. I'm sure whatever the results my methods and results will be questioned/insulted/deemed false by the side it offends but I'm ok with that. The results are really just for my curiosity and information but I'll do my best to document and share what I find.


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## Ziggythewiz (May 16, 2010)

I'd like to see all cells tested for sag and capacity at their rated values, as well as the rated values of the competition.

It would also be interesting to see how similar a stepped charge curve would be, where instead of just discharging and charging from full to empty and back, you stop every 5% of SOC to rest for a bit.

I'll be getting a PL6 soon to do some testing with CA40s SE40s, and lead


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## rwaudio (May 22, 2008)

Ziggythewiz said:


> I'd like to see all cells tested for sag and capacity at their rated values, as well as the rated values of the competition.


That shouldn't be a problem as both cells appear to be rated for capacity as 0.3C discharge or 30A which I can do.



Ziggythewiz said:


> It would also be interesting to see how similar a stepped charge curve would be, where instead of just discharging and charging from full to empty and back, you stop every 5% of SOC to rest for a bit.


I can do that as well, but to be clear I would basically use the PL6 in monitoring mode, and charge the cells (in series for consistency) stop the charge, wait awhile, continue charging, repeat and see what the results are?
What would you like to see from this?


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## Yukon_Shane (Jul 15, 2010)

It would be interesting to see some Sag vs. temperature characteristics for these different cells. I'm noticing what appears to be significantly lower sag in my thunderskies when they are really warm (like 40-50C); however, it would be great to see this varified with some real data (rather then me trying to stare at a display while I've got my foot to the floor).


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## rwaudio (May 22, 2008)

Yukon_Shane said:


> It would be interesting to see some Sag vs. temperature characteristics for these different cells. I'm noticing what appears to be significantly lower sag in my thunderskies when they are really warm (like 40-50C); however, it would be great to see this varified with some real data (rather then me trying to stare at a display while I've got my foot to the floor).


Hmmmm... I can probably do a few datapoints, fridge/freezer cold, house ambient, and if I'm lucky ~30degrees. It would be a "more controlled" environment but I think the only data from that would be how those cell types compare to eachother. For that test I think it would be worthwhile trying to get the Yellow Thundersky 100Ah in there too.

We'll have to see how much time I get to spend with these cells...

I might be able to add a 40 and 60Ah Sinopoly to the test.
That would make it 40/60/100Ah from BOTH Sinopoly and CALB CA.


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## EVfun (Mar 14, 2010)

I think voltage at the end of 5C for 10 seconds at about 50% SOC would be useful information. This would help show real world sag. Of course it would take a big load to handle it.


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## rwaudio (May 22, 2008)

EVfun said:


> I think voltage at the end of 5C for 10 seconds at about 50% SOC would be useful information. This would help show real world sag. Of course it would take a big load to handle it.


It might not be exact, however that could be done in the car. I think I'm going to need an assistant with a check list to run down the different processes and take a time reference that can be used to go back on the PL6 log to match up data with activity...


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## jumpjack (Sep 9, 2012)

A lifecycle test at 1C would be very cool.
But I think it would require too much time/money, isn't it?
I mean, we all know LiFePO4 batts allow 1000 or 2000 cycles... but at just 0.3C or 0.5, while into an EV they are used at 1C or 2C; but how long will they actually last at such rate?


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## rwaudio (May 22, 2008)

jumpjack said:


> A lifecycle test at 1C would be very cool.
> But I think it would require too much time/money, isn't it?
> I mean, we all know LiFePO4 batts allow 1000 or 2000 cycles... but at just 0.3C or 0.5, while into an EV they are used at 1C or 2C; but how long will they actually last at such rate?


No life cycle or destructive testing here, this is more of a simple comparison between the brands under the same conditions. Some people keep saying that CALB has better current output, others say Sinopoly is just as good, I'm just testing them together and see what happens. These cells belong to friends of mine so they will get a few test cycles and be returned.


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## skooler (Mar 26, 2011)

All sounds good. If you need some help getting hold of some sinopoly's let me know. I gave Jack Rickard four 200ah cells for testing (which never happened). I'm sure they could find their way to you!

I also have some 60s and 100s in the UK and am planning to be in the states so could arrange getting them to you if you'd like?


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## rwaudio (May 22, 2008)

skooler said:


> All sounds good. If you need some help getting hold of some sinopoly's let me know. I gave Jack Rickard four 200ah cells for testing (which never happened). I'm sure they could find their way to you!
> 
> I also have some 60s and 100s in the UK and am planning to be in the states so could arrange getting them to you if you'd like?


Thank you for the offer, I'd prefer not to commit to extensive testing, this came more out of an opportunity than anything. A local EV'er just got a lithium upgrade to Sinopoly 100's in his 914 (the car is being painted, so borrowing a few cells works due to timing) and another local EV'er ordered a few extra cells to make a set of CALB's when he ordered the 60's for his lithium upgrade 40/60/100.

I have a 40Ah CALB, a collection of 60Ah CALB's (83 Cells), a 100Ah CALB, and four 100Ah Sinopolys, another friend of mine about 3 hours away has a 40 and 60Ah sinopoly that may be worth bring down for direct comparison but doesn't have to happen at the same time, I will always have access to CALB 60's and the 40 should also be available. I also have A123's as an extra data point.

What I'm really trying to get out of this for my own knowledge and the ability to advise others in purchasing decisions is simple.... What's better? Are they the same? Do you just pick the one that you can get the best price or has better availability?

My friend with the Sinopoly 100Ah pack in his 914 is disappointed in the performance of the car mainly because of the configuration settings put in place buy the person who installed the pack. It's a zilla 1K LVwith 48 cells but the maximum battery current is 300A, (the rated continuous current of a Sinopoly 100) he say's the car performed much better on lead. Well that shouldn't be, lithium should be an upgrade in all respects. I'd like to find out if the 5C burst rating for the Sinopoly's is accurate, can you safely go a bit further? 6C? 10C?

I currently have my CALB 60's (including 18 A123's) 92 cells (soon to be 101) set to a maximum of 750 battery amps, and although I've only hit that a hand full of times and only for a couple of seconds, it gives my car incredible performance. 

I'd like to see if we can set the 914 up with 500 battery amps, or maybe 750 or even 1000 if they match the peak current the CALB's are capable of for bursts. I'm not testing the impact this will have on lifespan, however my car will be an indicator of this as the years pass.

The friend I have in Edmonton has to purchase his pack in sections a year or so apart, so he would also like to know if a 40Ah 100 cell pack of Sinopoly cells would give decent performance in a 3300lb car or if the battery current limits make it impractical. Then supplement it with a 2nd string of 100 40Ah cells later.


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## Yukon_Shane (Jul 15, 2010)

rwaudio said:


> ....My friend with the Sinopoly 100Ah pack in his 914 is disappointed in the performance of the car mainly because of the configuration settings put in place buy the person who installed the pack. It's a zilla 1K LVwith 48 cells but the maximum battery current is 300A, (the rated continuous current of a Sinopoly 100) he say's the car performed much better on lead....


How people choose to treat their batteries is obviously a matter of personal preference/opinion but 300A max from 100Ah Sinopoly pack seems pretty conservative. At 48 cells that's probably only about 60hp max, no wonder he's disappointed in the performance.

I have a 100Ah Winston pack (probably a pretty close comparison to the Sinopoly's) of 50 cells that I regularly pull 400amps and occassionally 500 amps out of with no problem. I can't comment on how this effects life expectancy but as long as the pack is relatively warm the voltage sag is very reasonable.

As per my previous request though you should try and measure temperature when you're doing this testing or atleast try and keep all the cells you're testing at a constant ambient temperature to ensure you're comparing apples to apples. My pack seems to only sag around 15-20% at 5C when it's nice and warm (40 degrees C) but at anything close to 0 degrees C the sag starts to get really bad and around -20 the car is undrivable without giving the batteries some heat.


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## rwaudio (May 22, 2008)

Yukon_Shane said:


> How people choose to treat their batteries is obviously a matter of personal preference/opinion but 300A max from 100Ah Sinopoly pack seems pretty conservative. At 48 cells that's probably only about 60hp max, no wonder he's disappointed in the performance.
> 
> I have a 100Ah Winston pack (probably a pretty close comparison to the Sinopoly's) of 50 cells that I regularly pull 400amps and occassionally 500 amps out of with no problem. I can't comment on how this effects life expectancy but as long as the pack is relatively warm the voltage sag is very reasonable.
> 
> As per my previous request though you should try and measure temperature when you're doing this testing or atleast try and keep all the cells you're testing at a constant ambient temperature to ensure you're comparing apples to apples. My pack seems to only sag around 15-20% at 5C when it's nice and warm (40 degrees C) but at anything close to 0 degrees C the sag starts to get really bad and around -20 the car is undrivable without giving the batteries some heat.


I thought the 300A setting was a bit too conservative as well, in the testing I'm doing I hope to see if 500A+ is ok.

As for the cold weather testing, I think I'll do a 40A discharge test at fridge and freezer temps... IE charge them up full or 50%, put them in the fridge/freezer and do a discharge test. I won't attempt to keep them cold, they should be allowed to warm up as they would assuming an insulated battery box in a vehicle.


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## rwaudio (May 22, 2008)

So I now have a 40/60/100 each from CALB and Sinopoly (thank you Darryl, John, and Wade)

Lets start with the physical:
The 40's and 100's are dimensionally pretty close, the 60's... well they are both rated at 60Ah. 










And on to the weights:

CALB 40









Sinopoly 40









CALB 60









Sinopoly 60









CALB 100









Sinopoly 100


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## rwaudio (May 22, 2008)

I had done some testing with the PL6's and 100Ah cells, I wasn't happy with the graphs and the differences between my pair of PL6's so now with the other cells on hand I've decided to revise the testing method slightly.

Each cell will be discharged to 2.5v cc-cv, then the pair (one CALB, one Sinopoly) will be put in series and run through a charge/discharge cycle using a single PL6 in a single test so the graphs come out properly and the results aren't off based on possible differences between my two PL6's.

I'm not sure if I'm going to allow the PL6 to balance the cells at the top or not, since capacity of such a small sample group probably doesn't bring significant value to the test. If there is a significant variation between the cells I have I'll mention it.

I'm more interested in IR and the charge/discharge voltage curves for this part of the test.

For the first round anyway all cells regardless of capacity will be tested at 40A. If I have time I'll try and follow that up with a 0.3C charge/discharge because that is how all of the cells are rated, in that test I will measure capacity.


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## Old.DSMer (May 18, 2012)

Very nice and looking good. Thank-you!

FYI - Sinopoly does make a 60Ah with dimensions closer to the CALB CA. It is called the "B" model -- 60Ah(B).


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## rwaudio (May 22, 2008)

40Ah cells:

Observations:
-The Sinopoly Data sheet is more informative, contains more and better graphs and includes important (to me) data like impulse current and duration.
-I like the look and feel of the CALB cell better.
-CALB has better markings for + terminal (red) vs Sinopoly both black, easiest way to tell on the Sinopoly is the aluminium vs copper terminal. (but you still have to remember which is which)
-Sinopoly serial number and other markings are much better, they are printed in a groove on the plastic casing on both sides of the cell, unlikely to wear off long term.
-CALB serial number is on a small sticker, the ink easily wears off and the sticker can easily tear or fall off.

Data sheet vs actual:
Weight
Sinopoly within tolerance
CALB 0.1kg heavier than spec 
Actual weight of the cells is the same.

Capacity
Sinopoly over spec, matching discharge curve on data sheet at 1C
CALB under spec, falling 5-7Ah below data sheet discharge curve at 1C

PL6 calculated IR 
I won't quote numbers as my pair of PL6's don't agree, however during this test using one PL6 for both cells the CALB was 20% lower than Sinopoly, however during the discharge phase the cell voltage of the Sinopoly was alway higher than the CALB at 40A. The Sinopoly is coming in at around 44Ah where the CALB wasn't able to make 36Ah.

Is the CALB defective? I don't know but those are the results.
Discharge voltage shown below, Sinopoly is cell 1 CALB is cell 2

I'll post more graphs later.


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## Ziggythewiz (May 16, 2010)

Cool pics and info! I hope to do some soon too, mostly on CALB 40s.


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