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FrozenGate by Avery

Redilast Li-ion Battery sales! High quality - Made in Japan / Korea! 10% off!






Got a little more feedback on my CPF thread for you guys:

"I've finished comparing the Redilast 2900mah cells (protected) to the Panasoninc NC18650 2900mah (unprotected) cells and they perform exactly the same - come off the PILA IBC charger at the same voltage, take the same length of time to charge (+/- a couple) of percent, same amp draw (2.1A which is WAY higher than the 1.5 my Trustfires were giving - now scrapped btw) on my MG P-Rocket and the same run time (again, +/- a couple of percent). On the Redilast cells I tested them in a Quark Turbo with an 18650 body and I can confirm they cut off when the voltage reaches 2.5v.

Very impressed - all the benefits of the excellent Panasonic NCR18650 cells with a protection circuit (that seems to function correctly as far as I can tell)!

I think I'll be putting in an order for a few more."

-amigafan2003 (CPF)

Redilast Li-ion Battery sales! High quality - Made in Japan / Korea! 10% off! - Page 2 - CPFMarketPlace
 
jasonck08 said:
All of my cells are made by Top companies (ie Samsung, Sanyo, Panasonic) where most if not all of AW's cells are made in China.

All of my IC (Integrated Circuits) are made in Japan, so the cell will always properly terminate within specs.

I've tested AW's cells and I've had some of his cells down to 2.2-2.3v under load with the PCB never tripping! Over discharging a cell is very bad for it!

.
Click to expand...

To be fair, AWs newest cells are also based on the Japanese Panasonic NCR18650 cells. In addition he brought us the IMRs. My personal experience with AWs batteries have been excellent, and he stands behind his product as well.

Being as your product is the newcomer to the block, it will have to prove it self to me first, but I am willing to listen. There appears to be only 1 data sheet, on the 2600 cell, none on the other two, and it pretty obviously was made by you. What sample size did you test for those results? What equipment are you using for your discharge tests?

Are your 2900 cells definitively the Panasonic NNPs? Since these aren't strictly a LiCo cell, any different safety instructions?
 
vegasf6 said:
To be fair, AWs newest cells are also based on the Japanese Panasonic NCR18650 cells. In addition he brought us the IMRs. My personal experience with AWs batteries have been excellent, and he stands behind his product as well.

Being as your product is the newcomer to the block, it will have to prove it self to me first, but I am willing to listen. There appears to be only 1 data sheet, on the 2600 cell, none on the other two, and it pretty obviously was made by you. What sample size did you test for those results? What equipment are you using for your discharge tests?

Are your 2900 cells definitively the Panasonic NNPs? Since these aren't strictly a LiCo cell, any different safety instructions?
Click to expand...

My 2900's are 100% based off the Panasonic NCR18650 cells. I'm not sure what IC AW is using on his 2900's, but in the past his 2600's and other cells used pretty low quality IC circuits that do not reliably trip at the recommended voltage. I have 2 of his 2600's and they seem to trip around 2.3v, which is way overdischarging the cell when its rated at 2.75v cutoff. The IC's I use on my cells are the highest quality you can get... made in Japan, just like the cell itself!

Secondly, the only data sheet I have posted is for the 2600 Cell. The graphing was done on a Computerized Battery Analyzer. The tests posted for the 2600 cell was a random sample. I did not hand pick the one with the best performance. All the cells have very similar performance though +/-2% or so.

The reason I have not posted other datasheets yet is because I sent in my Computerized Battery Analyzer to be calibrated for higher accuracy (before it was reading .04v low) on all the graphs, so the results will be even better once I re-do my tests.

TheMonk said:
Run time of the Redilast 2900mah tested at light-reviews, very close to the Ultrafire 3000mah.

http://light-reviews.com/forum/download/file.php?id=772&mode=view

Light-Reviews.com • View topic - Li-Ion 18650 shootout
Click to expand...

Yes they are in that test, but it’s not a very accurate test because it only shows the story from a random flashlight with a driver board. A proper test would include discharge tests at various currents .2C, .5C, 1C and 2C. As well as a test of the cells capacity after 50 or 100 cycles. I highly doubt the UF cell would last that long before completely failing (or exploding or leaking).

Also keep in mind the quality of the UltraFire 3000 is questionable to say at the least. Here is a link to a leaky cell and a cell that exploded:

Light-Reviews.com • View topic - !WARNING! UltraFire BRC 18650 3000mAh (Leaky and Rusted cell)

Ultrafire 18650 3000mA exploded - CandlePowerForums (Exploded cell)
 
I see. The West Mountain CBA? Incidently, I didn't realize the CBA III was out, I was under the impression the II was the newest model. Which are you using? Those are nice devices, I am stuck using my iCharger, though its not bad either.

Yes, the test posted using just a flashlight was not the best data, not even a constant current test to extrapolate run times from. But, data is data, better than nothing.

I would imagine the cell manufacturer has provided white sheets, done testing of there own. But, perhaps to reveal those would give away trade secrets? Can you reveal if the cells, and the protection circuits have undergone any test by U.L, J.I.S., C.E. etc?

I hope Silverfox or Luxluthor undertake some testing.
 
Ok, got my answer here instead.
CBA voltage accuracy - CandlePowerForums

I see some interesting discharge graphs here:
IMR vs LiCo @ 5A - CandlePowerForums
Looks as though when you were testing the Sanyo 2600 vs The AW, AW just beat it out in runtime, though the Sanyo appeared to have less voltage sag. Thats a good thing, especially in a boost circuit, though maybe not so much so in a linear or buck.

Apparently the Panasonic doesn't hold its voltage so well at 5A either. Your sample of AW IMR wasn't too impressive, was it?

Also, question about the protection circuit listed on the datasheet posted for the 2600mAH Sanyo/Redilast cell. I was quite surprised at your decision to use a protection circuit that allows 7-8 amps! That would be AT LEAST a 3C discharge. Actually, I am confident it would be higher seeing your discharge graph at 5A only managed 2.35 AH. At 8 amps I doubt the cell would manage 1.75 AH. At that rate, your protection circuit would allow a theoretical 4.5C discharge rate.

Wouldn't you agree that is extremely dangerous? I would just as soon have an unprotected cell than that false sense of security.
 
Hi, sorry I haven’t checked this forum in a few days or had much time to respond.

The Panasonic cell does quite well at heavy discharges. It is a 3.6v nominal cell, with a 2.5v cutoff (it’s not your typical 3.7v nominal, 2.75v cutoff LiCo cell). If you take that into consideration and view the 5A graph, it did pretty respectable. A sign of a cell struggling at high discharges is when the capacity of the cell varies more then 10% from a .2C discharge to a 2C discharge.

Secondly, I didn't have much choice for the protection circuit. It was either limit things to about 4-4.5A max (less then 2C), or use a circuit that allows for 7-8A. I did not want to limit my cells uses, as a lot of the guys at CPF run these cells from time to time with high powered hotwires that may draw up to 2C.

While I would never recommend discharging a LiCo cell at greater then 2C for any length of time, doing a discharge at 3C on a quality cell should not cause it to explode or vent, but instead will damage the cycle life and capacity of the cell.

Keep in mind that the protection circuit doesn't just have overcurrent protection, but also provides shortcurit protection, overcharge protection and overdischarge protection. Pretty much all LiCo cells also have some type of PTC protection, where in the event of an overcurrent or short circuit situation the cell will shut itself down (this is independent of the PCB)
 
jasonck08 said:
Hi, sorry I haven’t checked this forum in a few days or had much time to respond.

The Panasonic cell does quite well at heavy discharges. It is a 3.6v nominal cell, with a 2.5v cutoff (it’s not your typical 3.7v nominal, 2.75v cutoff LiCo cell). If you take that into consideration and view the 5A graph, it did pretty respectable. A sign of a cell struggling at high discharges is when the capacity of the cell varies more then 10% from a .2C discharge to a 2C discharge.
Yes, the new nickel oxide based Panasonic is a very interesting creature, and bears more investigation. Besides the fact that it holds up better to the 5A load (it should, partially because of its capacity and because of its chemistry) it also appears to be a safer make up. Here is a link to panasonics page about it for those that would like to read it:
News | Panasonic Industrial Solutions Europe
Note they also have the NCR18650A at 3100mAh too! Nice energy density levels on it.
Also, here is a link to an unwrapping:
RediLast Battery Unwrapping - CandlePowerForums
I had been in touch with Lux earlier in the week and he had planned the same thing. Nice we get to see the guts.

Secondly, I didn't have much choice for the protection circuit. It was either limit things to about 4-4.5A max (less then 2C), or use a circuit that allows for 7-8A. I did not want to limit my cells uses, as a lot of the guys at CPF run these cells from time to time with high powered hotwires that may draw up to 2C.
So, all the cells use the same protection circuit? While the 6-7 amp discharge (or 7-8A as now stated) may not be too much of a burden for the Panasonic cells, it is certainly pushing it for the Sanyos. THis is the source for the 6-7A numbers.
18650 Protection circuit amperage kick in? - CandlePowerForums
While I would never recommend discharging a LiCo cell at greater then 2C for any length of time, doing a discharge at 3C on a quality cell should not cause it to explode or vent, but instead will damage the cycle life and capacity of the cell.
Perhaps. But, continued discharge of 3C or even greater will permanantly increase the cells resistance, hence causing heat while discharging. Over time the effect will multiply. This would cause a rapid decrease in cycle counts, but could also casue the cell to enter thermal runaway and vent with flames. Of course, as the cells age the capacity will go down and what was once a 3C load will become a 4C load etc.
Keep in mind that the protection circuit doesn't just have overcurrent protection, but also provides shortcurit protection, overcharge protection and overdischarge protection. Pretty much all LiCo cells also have some type of PTC protection, where in the event of an overcurrent or short circuit situation the cell will shut itself down (this is independent of the PCB)
I consider a battery with ONLY a positive temperature co-efficient to be an unprotected battery. The external protection cell is vital in the case of an unmonitored battery, like we are using here, or at CPF. However, the short circuit protection provided by the PCB is only in the case of external shorts. Keep in mind an internal short can still happen.
Click to expand...
Thanks for taking the time to reply.
VegasF6

*edit* Looks like Lux did test the cell, just didn't need to do the unwrap as it was done by csshih.
http://www.candlepowerforums.com/vb/showthread.php?p=3537377#post3537377
 
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