I am wrong about MaxAmps.

[lincpimp]

As far as my "bashing" goes, well it is my opinion.

On the subject of magazine polls, I would like some info about the people who polled. Have they owned and used packs from maxamps and all of the other lipo mfgs? Most likely not, as people do not like to spend thousands of dollars on batteries. And most people who participate in online polls have nothing better to do.

I have bought a lot of batteries, and do not have many maxamps packs left. I have tested all of them and settled on the packs that I found to perform the best. I am not emplyed by any battery mfg, and have not got any freebies either.

Austin, good luck with your business, I am also a business owner and understand your issues. I am sure you will continue rasing the bar, you have to in order to be competitive. Just be careful how your employees make you look!

[DrKnow65]

Austin, how about a discharge graph? I mean if it's all on the level, and your packs are so improved since last year, wanna throw us a bone?

I'm not a hater or sponsored. Just a guy who will be replacing a lipo pack that is less than a year old, been replaced twice already, and after the last time it quit working, I took it apart myself and have the dead cell is sitting on the counter. My 3S is now a 2S and I'd like to only spend the cash on a reliable replacement. I won't name the manufacturer, but I will say that it was most certainly still under warranty when I decided I would rather fix what was left of it than wait for the fourth potentialy flawed pack.

I have seen other manufacturers and sights with discharge graphs, why not post it? I mean you guys must test the cells once in a while right? mabey each time to get a newer better cell?

What cell do you want to see specifically? This is a new version of the 4000 cell vs the old version. The factory rates it at 4200mah. We rate it at 4000. This is the same cell that we use in our 8000 packs. At 20C, you can see that it holds what I would consider great voltage. I don't know how you could not call it a 20C constant cell based on the data...

-Austin

And here is the 3000 cells that we use for the 6000mah packs.

-Austin

I have a hard time releasing these because it gives our competitors an idea of exactly what they need to compete. As I have said many times, our pack quality and performance is second to none. The proofs in the graphs. I have not seen a 3000 cell or a 4000 cell on the market that will compete. If there was one, we would offer it.

-Austin

[DrKnow65]

Fair enough

Guess I need to get an eagletree data logger and figure out how many amps my 3.5lb 4wd 1/10 buggy is pulling ... I have had 2 3S 5000mah packs give out on this car running a MM and a 5700kv motor.

The most recent failure (and I believe the same failure that happened to the last pack but I didn't open that one up) was one of the cell's tab burning off. I'll post up a pic here in a bit.

The first batt I got wouldn't balance. Guess I must have just been in the small percentage of factory defects 3 times in a row...

[DrKnow65]

Edit, forgot to say thanks for posing up the graphs. It feels funny that so many people have askes sop many times with no responce, I ask once and here they are hahaha. Suppose I should have asked sooner :)

[DrKnow65]

[lincpimp]

I had the same thing happen with a few cells. I often doubt that the thin tabs can hadle the current, especially when it gets over 100amps.

[aqwut]

Thank You Austin, TBH..
You are absolutely correct!! As a company grows, more people will lash at you. But after your explanation of the tronics cells, I understand. And I'm aware that LiPo cell technology are always improving. It doesn't take much to calm down a situation. I personally think Jason should just quit calling people a Liar. I have never thought about never buying MaxAmps packs again, until Jason replied to my post in the manner which he did. Maybe it's a good thing that he has a lot of pride in the MaxAmps product, but you can't just push this thought or opinion to everyone who has a difference of opinion. Thank you for the explanation, and especially the graphs...

[DrKnow65]

Is it possible i've hit 250amps with this rig?

Specifically a Team academy SBV2-Pro 1/10 4wd buggy, MM/5700Kv, 5000mah 3S, 15/86 gears (around 78mph on BrianG's speed calc)

I would think the tabs would have to conduct the burst rating of the pack. I mean the sustained rating is 150amps, and the continuous is 100...

So far this is the best arguement for high voltage I have seen. No matter how good the cell is, if the tabs can't handle the load, better run more volts and less amps.

[johnrobholmes]

Awesome! Graphs! It might be my monitor, but could you blow them up a bit so I can read the numbers? Any temperature data and 1c, 10c, 15C graphs for comparison would be nice too. Especially temperature that is needed to duplicate these rates.


It is really nice to see some data finally, bravo Austin.

[lincpimp]

Originally Posted by DrKnow65

Is it possible i've hit 250amps with this rig?

Specifically a Team academy SBV2-Pro 1/10 4wd buggy, MM/5700Kv, 5000mah 3S, 15/86 gears (around 78mph on BrianG's speed calc)

I would think the tabs would have to conduct the burst rating of the pack. I mean the sustained rating is 150amps, and the continuous is 100...

So far this is the best arguement for high voltage I have seen. No matter how good the cell is, if the tabs can't handle the load, better run more volts and less amps.

Sike and I came to the conclusion that there is no way that the thin little tabs could hadle the spec discharge numbers, just not going to happen. High voltage is a much better way to go. My 8s savages with the 14xl feigao runs 3600 12c poly rc packs (around 45 amps cont) and has no issues. Motor gets to around 140 and stays there for a 30min run. The 60 amp esc barley gets warm, maybe 110, and the batteries are around 105 when the run is done. It is a heavy truck, and has plenty of power, more than my 7xl 4s revo.

[johnrobholmes]

Looking at the graphs a bit harder here, it seems that the average voltage is around 3.6v/cell. Wouldn't this indicate that running them at 20C is not the max continuous rating, and that they could be pushed quite a bit harder? But at the bottom of the 3.2a/h cell graph it shows 12a/h on the discharge?


edit: my eyes hurt, I will wait for you to enlarge them before I try to read any more

[DrKnow65]

I'm with you there JRH, I put it on photoshop 11 and blew it up, cleared it up as best I could, and still can't make out the numbers well enough.

Linc, It's just hard to fit HV into this little buggy. I need to get a better understanding of how to calculate the wattage different KV motors pull at different voltages. I do have a 2300KV ammo motor that I turned the shaft down to 3.2mm and use in this buggy to make it more raceable on the micro track at the nearest hobby shop. I guess I could get a 5S pack to get the performance back, but can I find one that will give me similar performance to the 5700/3S/5000mah and not weigh a ton?