Maxamps and Neuenergy lipo testing

[lincpimp]

Well, as far as comparing the two mfg packs, that is not really the point of my test. I am comparing the stuff inside the heatshrink, to the little sticker with the writing on it that is stuck to the heatshrink.

My main point is to esablish what kind of discharge these packs can hadle and still retain voltage. My seat of the pants testing seems to point to the enerland cells holding voltage better under load, but I would like some hard data to support this. I may continue testing past these two packs, but lack the variety of maxamps packs I once had.

[skellyo]

I think that linc has more than enough experience for us to draw reliable conclusions based on his methods of testing. All I really need to see is an Eagletree plot showing how far the voltage dips on high current peaks. A few data points of that and it's quite easy to determine which pack holds voltage better under load.

[lincpimp]

Originally Posted by skellyo

I think that linc has more than enough experience for us to draw reliable conclusions based on his methods of testing. All I really need to see is an Eagletree plot showing how far the voltage dips on high current peaks. A few data points of that and it's quite easy to determine which pack holds voltage better under load.

And this is what you shall get. I hope that my test vehicle and methods will yeild enough load to properly test these packs. I can always gear for 80mph or something stupid like that. That should provide enough load...

[glassdoctor]

This isn't the first time a Maxamps pack has seen a datalogger. I have posted several here before in a similar "test" session.

I don't even recall what the #'s were or what thread it's in, but I do recall that some were skeptical because the Maxamps packs did better than they were "supposed to", based on their very low opinion of them, lol. *cough*serum*cough* hee hee

My Kokam 20C 4800 posted better #'s than my Maxamps 5000, but it wasn't night-and-day between them.

I would expect a good 25-30C pack would also perform better than the maxamps pack.

Off topic: I do find it interesting that some here tend to say the TrueRC packs are ok but Maxamps are not. Of course, the TrueRC are a lot cheaper.... but certainly are not better packs. Perhaps you should pick up a TrueRC bargain pack to compare also. ;)

[lincpimp]

Originally Posted by glassdoctor

This isn't the first time a Maxamps pack has seen a datalogger. I have posted several here before in a similar "test" session.

I don't even recall what the #'s were or what thread it's in, but I do recall that some were skeptical because the Maxamps packs did better than they were "supposed to".

My Kokam 20C 4800 posted better #'s than my Maxamps 5000, but it wasn't night-and-day between them.

I would expect a good 25-30C pack would also perform better than the maxamps pack.

Off topic: I do find it interesting that some here tend to say the TrueRC packs are ok but Maxamps are not. Of course, the TrueRC are a lot cheaper.... but certainly are not better packs. Perhaps you should pick up a TrueRC bargain pack to compare also. ;)

Do you remember what maxamps cells you tested? Their 4000 cells seem to be decent, still not 20c, while I did not think that the 5000 cells were very good, maybe 15c before the voltage dumps. My trakpower 4900 packs easily outperformed a pair of maxamps 5000 2s packs in series. And the ratings of both are almost identical (my trakpower packs are the older 20c rated ones). The differnece was very obvious to me, and I did not think it would be that obvious. I must have picked up 2-3mph top speed, and acceleration was much better.

I have a feeling that Truerc packs are consider good due to their price to performace. I may have to pick up a truerc pack for testing, any idea what to buy?

[kulangflow]

The True R/C guy said that he uses the same cells as MaxAmps when I talked to him a year ago or so. I think the difference is that he advertises them as 15C at a lower price compared to MA's 20C at a higher price for the same cells.

[lincpimp]

Originally Posted by kulangflow

The True R/C guy said that he uses the same cells as MaxAmps when I talked to him a year ago or so. I think the difference is that he advertises them as 15C at a lower price compared to MA's 20C at a higher price for the same cells.

This is very interesting. I may have to pick up a 4000 3s pack to test, and maybe a 5000 3s pack if they sell that. I may have to give him a call and talk to him about his matching methods, or whether he buys the packs pre-assembled.

[kulangflow]

Linc, how do you determine what the true C rating of a pack is?

I have an Eagle Tree now and I'd like to test my MaxAmps packs to see how they do.

Do I just run them hard from full charge to LVC then do some kind of calculation from the data pulled?

[Serum]

get a 2P pack of the true-rc packs; Dans 4000 mAh cells are good. (for a very low price)

[lincpimp]

Originally Posted by kulangflow

Linc, how do you determine what the true C rating of a pack is?

I have an Eagle Tree now and I'd like to test my MaxAmps packs to see how they do.

Do I just run them hard from full charge to LVC then do some kind of calculation from the data pulled?

Well, from what I have read, run a full pack thru and post the graph. What I am looking for is what amp load pulls the cell voltage down below 3.5v. I figure that if the pack cannot handle its rated load with cells dropping below 3.5v it is not correctly rated.

What maxamps packs do you have? And what setup do you run these packs on.

[glassdoctor]

I ran 5000, 6000, and 8000 Maxamps packs. The 5000 had the edge in general considering capacities and voltage drop. But the 3000/4000 based packs were not too bad.

I was running them in my 8ight I believe.... just brief tests to get some amp spikes.

The big thing is the temp of the packs. Cold packs put up crappy #'s. Nice warm packs like on hot summer day put up much better #'s.

[glassdoctor]

I actually hesitated to recommend maxamps packs until I ran those tests and was pretty happy with the results, on top of the fact that they seem to run great in my cars and I've never had one get hot/puff on me. (except a pack that I shorted out.... my bad, and the reason why I don't have a 4s 5000 pack anymore)

[kulangflow]

Originally Posted by lincpimp

Well, from what I have read, run a full pack thru and post the graph. What I am looking for is what amp load pulls the cell voltage down below 3.5v. I figure that if the pack cannot handle its rated load with cells dropping below 3.5v it is not correctly rated.

What maxamps packs do you have? And what setup do you run these packs on.

(4) 2s 6000
(1) 2s 5000
(1) 3s 5000 - A cell appears to have died, so this will likely soon be a 2s 5000
(1) 2s 2100 - Axial AX-10/bl-RC18MT
(1) 2s 1550 - Vendetta ST(currently stock, bl on order)
(1) 3s 1550 - Axial AX-10/bl-RC18MT

The larger packs run in a few different vehicles:

-Stock 3905 E-maxx
-BL-Revo (MM/9XL)
-Kyosho Kanai 3 (MM/8XL)
-CRT.5 (MM/CC4600)
-RS4 (Sidewinder/CC5700)

I just confirmed with Dan of TrueRC that his cells are the same as MaxAmps.

[Arct1k]

I can help too if you you don't have any of the following batteries I have:

(2) 3s2p 4200
(2) 3s 5000 - 1 brand new
(2) 2s 5000
(1) 2s 4000
(1) 2s 1100

I can run any of the bigger packs through my CRT .5 / 7L 16/46 with an eagletree...

LMK

[lincpimp]

Certainly, any info that you guys can provide will be very useful. I only ask that you try to load the batteris as much as you can. At least to the cont rating for a few seconds to get a good measure of voltage drop.