Riketsu

iTrader: (34)

Also, what load (amps) did you use to test the batteries?? Did they perform in the similar fashion when you varied the load??

R1wurks

iTrader: (1)

i've never tested "newer" revtechs & fantom, if im guessing yes!

R1wurks

iTrader: (1)

i prefer not to talk about that, there's too many opinions about how the test should be done & just wont have the time to defend our theories.

what i can assure you is that, we tested almost all the levels of discharge. we raised the amp draw until we can visually see a significant difference between a good cell & a bad cell.

Riketsu

iTrader: (34)

Correct me if I'm mistaken, but the way I understand it, it is not a logview. mAH is calculated as a cumulative multiplication between amp draw and time.

Edit: Woops, I thought you were talking about the type of graph, not the program. My mistake!

R1wurks

iTrader: (1)

It's not logview, it' a program that was originally made for cba mountain radio. We just use this software since its the only one capable of doing an overlay.
Not sure how it would work on logview.

sosidge

I'll hazard a guess that the discharge rate is in the region of 30A, based on the discharge unit I think is being used.

And to be honest, all those graphs say to me is that the generic pack has a weak cell in it (either as a result of it being a cheap pack, or coincidence), and the other packs perform very similarly. The slightly lower average voltage of the CRC pack can be explained by it's lower capacity.

I have no idea what 12th mod uses from a 1s in 8 minutes, but 1/10th TC in 17.5 Blinky uses about 1500mAh, that's 1/3rd of the rated capacity of my IP shorty pack, and 1/4 of the rated capacity of my IP-made stick pack. I'll never see the voltage drop. When I race, I notice that the car is quicker in the first minute or so - this is a combination of the higher pack voltage and the lower motor temps. My cars stay consistent for the remaining 4 minutes, any drop off is caused by motor heat rather than a weak battery.

I'd have no concerns about any of those branded packs assuming the QC is consistent.

syndr0me

iTrader: (32)

There's like two different packs on the market. The rest is just different stickers.

R1wurks

iTrader: (1)

On tc it's different. I don't know any thunder power or crc 2s comparable to most 7000mah cells on the market (smc,reedy,protek,intellects sting & trinity/revtech . Most of this 7000 packs are capable of a tenth or two better lap times in most conditions, thruout a full 5 min race.

So I would have concerns with the some of the brand names, specifically crc 2s & thunder power 2s.

Try running a pack that was used on one 5 minute main & try hitting your best lap with the run Down pack(from a 5min main) with a cool motor.
If you can hit your fastest lap consistently with that pack then I agree with you.

R1wurks

iTrader: (1)

here's a comparison 2S 7000mah prototype VS thunder power 2S 6000 65C

the gap between the lines is equivalent to about a tenth on the first few laps & opening up to about two tenths after the first few laps.

Benzaah

iTrader: (24)

I know you guys are just coming through the winter in America but here in sunny Australia Its all about conditions. We had a 38c day with track temps hovering in the 60c mark on the weekend. I had 2 x 3 month old 100c Revtech packs swell after their second run of the day so IMO they are rubbish. These packs have been looked after and I'm very disappointed in them and feel like its $270 bucks down the drain! I used 2 x 6 month old Tp 65c packs in the same conditions with another 4 runs on each pack with zero swell issues. I suffered from Less punch which is a sacrifice ill make for a pack that does not puff in the heat.

daleburr

That doesn't look like any lipo discharge graph I've ever seen. I can only assume you're discharging at a very low rate. Under any kind of decent load the lipo voltage will drop immediately due to the load. For example on my motor dyno pulling around 40A, even a decent lipo immediately drops to around 8V.

You can see it here on a graph from the SMC test thread; the voltage drops as the load quickly ramps up at the start:



If you're going to publish test results, please be honest like Danny from SMC and publish the testing methods. Otherwise no one is going to take you seriously.

M7H

During the worlds, I had 1 6400mAh pack let me down, and could only do 7.54 minutes.

But in general, depending the track size, around 5000-5500 mAh.....
You have to put your cut-off at 2.8, or even 2.6V (under load), because otherwise the 8 Minutes is a challenge!, certainly if you are using a bit of boost timing.....

2wdrive

martin, how much mAh went back into the pack when you charged it?

M7H

Sometimes like 5800mAh... But the charger I used is not completely telling me the truth.

But because it has the capability to "calibrate" the end voltage, I used that on for the worlds, to get as close as possible to 4.20999999999999V

Now I'm going on my way to the Indoor track, care to come along tonight Alex?

R1wurks

iTrader: (1)

Yes we are discharging less than 40A (who said we are?), are you expecting the Thunder Power to perform better at 40A only?

If you don’t like our test then move on, this is not for you. This test is only for people that appreciate it & we don’t expect you to appreciate it. We also don’t expect you to take us seriously, go do you own test & post it.

You said please be honest? When did I lie?
This is my test & my opinion, if you think you can disprove it then feel free to do your own test.