Tony got the Point.
I remember a tech-discussion in germany regarding cells and oval rules half a year ago. There was stated, that with the extreme sensitivity of the current Generations (6,6Ah Aspec, etc.) at and above 60° watercooling could be an effective way to drive the whole capacity in a race without overheating/damaging the cells.
If it makes really sense in practice and how to get it ideally integrated (the temp dramatically rises in the end of capacity, for 80% of running time you do not want to cool your cells) is another discussion
Since this discussion rolls on I'd like to re-state my original point : (Like I told my Ex on our honeymoon):
"It's all how you look at it". If we're performance-sport or sprint racing, the setups are usually configured to not unduly tax the electronics. We know fairly accurately what our runtimes are and use enough mah capacity to allow some headroom. No need to cool the packs.
For the entry-level Atomic/Venom casual FE'er, it seems(from posts I seem to recall reading), extended runtimes are desired and THAT's where the batteries end up getting destructively hot and could benefit from cooling. And as my buddy Ralf alluded to, European racing employs much longer heats than here (Offshore excluded but...) and "..watercooling could be an effective way to drive the whole capacity in a race without overheating/damaging the cells."
I'm not defending nor criticizing the issue of pack cooling, only that by thinking outside our often narrow-minded frame of reference we can see points made from other directions.
2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
'11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono
Many of us use setups that don't put the batts in this kind of peril. Doing so does not guarantee a win.
Did i described that?
Originally posted by ray schrauwen
There are far better cells for the same $$ than A-spec.
They were an example for the generation of lipos.
Originally posted by ray schrauwen
So to make a battery cooler effective you may have to have a 3rd channel switch for a valve to incorporate the cells into the cooling cct. or have it's own separate system. Seems like if you just backed off your setup, you would not require this complication.
Another discussion for personal feels.
I explained a discussion which was going on because of the heat sensitivity and where it is coming from.
I do not care of that stuff, but the technical background makes it interesting.
Well fellas just think if this cooling of packs was applied to good batteries....then you might be on to something! Wait....if you actually have good batteries they don't need cooling muhahahaha!
I know I know...I got jokes...true story tho
32" carbon rivercat single 4s 102mph, 27” mini Rivercat 92mph, kbb34 91mph, jessej micro cat(too fast) was
Ray you can PM me the results of your testing pls ... we will keep it ... this is a good smile type thread.... Im going to make a thermostatically controlled sheath to put my lipos in, use water cooling and esc and motor heat, this will keep the packs at a constant peak temp of performance. So look out next yr
Tunnels-PS295. Cats-H&M M1 Supercat Daytona rivercat. Monos-DF Cyberstorm HiTech 29. Hydros- Ms K Vac-U-Pickle Custom built 37" shovel 10th scale converted to FE Shadow. Rigger-H&M Evo II. AQ Harbortug recovery boat. Build in progress 37" cf Dragboat
Ready for the next laugh, I had previously mentioned that I had asked on their site how could they be selling a watercooled lipo but it not be warranted against water damage...well they did finally respond
"A: Hello DJ,
These batteries are designed to be ran in conjunction with your boats contained cooling system. The battery is to be used inside of a dry boat hull. You will run this water-cooled battery inline with all of your other water-cooled components.
Thank you "
Now talk about not actually answering the question ..... Happy Turkey day guys
Forgive my ignorance (or perhaps lack of comprehension), but I'm not sure what you see wrong with their statement. It seems like a pretty reasonable answer to me. Many ESCs are water cooled and not warrantied in the event of water damage. I don't see where this is any different.
I also think that while this may be a gimmick for the most part, at least they tried something (although I remember maxamps doing this a couple years ago, resulting in a similar thread). The majority of lipo companies do little more than slap their sticker on a pack that someone else made and call it a day. There is nothing wrong with those companies, but I applaud the companies who go a little off the beaten path and try to offer something different.
I don't think this idea is as silly as many of you think it is, either. I think liquid cooled cells are a possibility, likely a probability in the near future. I don't know if they will become commonplace in models but in larger machines that need to run for longer periods of time it seems pretty logical.
I saw a few battery coolers at the Naviga worlds last year, water cooled plates to slip between cells in a pack allowing a slightly deeper discharge with similar (not quite death inducing) end of run temperatures to allow a little more average power during the race. The theory seems sound to me, but whether the little extra power outweighs the extra weight of the coolers is debatable, so until they are popular enough here for me to get a good sample of numbers from I will keep things simple and cheap and stick with my existing cutoff voltages and un-cooled cells.
With the aid of datalogging the temperature of the water motor, esc and the batteries it may be feasible to restrict the water flow enough to both heat and cool the LiPos, it is far too much time and effort for me to take on for something that may or may not be worth its weight, but I bet someone successfully does and I see the results in the next few years.
Originally posted by ray schrauwen
Many of us use setups that don't put the batts in this kind of peril. Doing so does not guarantee a win.
Same here Ray, I like my cells to last 2 seasons, so I don't fully empty them, but if I left the common 20% in the cells it would guarantee never getting a win.
Originally posted by ray schrauwen
There are far better cells for the same $$ than A-spec.
I'm sure that is correct for the racing that you do, but that is not the case for Naviga racing with our 280g/560g weight limit, there are better cells available from Redzone and Tenshock but they are more expensive, or there are competitive alternatives from ETTI, Desire, and Victory Batteries, but I believe them to be the same cells and you still pay more.
Originally posted by propperchopper
European racing employs much longer heats than here (Offshore excluded but...)
Propperchopper, Offshore isn't really an exception, we race for 6 minutes in Naviga, which is much closer than with your sprints, but we still need half as much runtime again. We also need to do it on only 560g (1lb 3.75oz) of battery for our equivalent of "P". What do the periods allude to, do some of your guys have trouble with hot cells puffing in Offshore too? What does a typical P offshore pack weigh? I guess most people run 2p? You limit capacity not weight over there right, what is it, are most folks near the capacity limit?
OMG, check out the only comment on the Maxamps review thread I posted above...............its at the bottom when you scroll down, but here it is...........
"How about a pump to deflate the packs when then puff ?"
Thats Hilarious, the only comment on their "new" product
"......Propperchopper, Offshore isn't really an exception, we race for 6 minutes in Naviga, which is much closer than with your sprints, but we still need half as much runtime again. We also need to do it on only 560g (1lb 3.75oz) of battery for our equivalent of "P". What do the periods allude to, do some of your guys have trouble with hot cells puffing in Offshore too? What does a typical P offshore pack weigh? I guess most people run 2p? You limit capacity not weight over there right, what is it, are most folks near the capacity limit? ...."
Paul, As far as the P class goes (which is where I mostly compete except for P-Ltd) ; A mill + 6-Lap heat on the 1/6 mile oval usually runs @ 2 1/2 minutes (barring penalty laps). Offshore is a 30 second full mill + 4 minutes.
In NAMBA P class the mah limit is 10,000. 4S2P is usually the norm. A single 4S2P weighs @ 540g.
I stopped entering P-Offshore with my P-Oval rigged Mono 'cause I worried that I'd draw my packs down too low.
The last time I entered P-Offshore I had a way propped down (to conserve mah) dual rudder Mean Machine which wasn't competitive.
The Ltd Offshore class uses motors drawing maybe 80A / 100A max so with 10Kmah on board no worries.
2008 NAMBA P-Mono & P-Offshore Nat'l 2-Lap Record Holder; '15 P-Cat, P-Ltd Cat 2-Lap
2009/2010 NAMBA P-Sport Hydro Nat'l 2-Lap Record Holder, '13 SCSTA P-Ltd Cat High Points
'11 NAMBA [P-Ltd] : Mono, Offshore, OPC, Sport Hydro; '06 LSO, '12,'13,'14 P Ltd Cat /Mono
I saw a few battery coolers at the Naviga worlds last year, water cooled plates to slip between cells in a pack allowing a slightly deeper discharge with similar (not quite death inducing) end of run temperatures to allow a little more average power during the race. The theory seems sound to me, but whether the little extra power outweighs the extra weight of the coolers is debatable, so until they are popular enough here for me to get a good sample of numbers from I will keep things simple and cheap and stick with my existing cutoff voltages and un-cooled cells.
So I am seeing it this way. Naviga rules have weight limits as I knew already so, add weight with coolers to your already setup boat that may be at max weight already, therefore you have to trim weight somewhere else...
Does anyone else see this as tail chasing? I'm not trying to be rude or condescending but, give and take is the quandary. Where do you take weight away from, cells, motor, hull, hardware?? I'm sure it's only a few grams or it could be more depending on the design.
What is in there anyway, just an aluminum plate or a copper plate or a water filling type like the ones hobby king sells?
Did Max Amps and or Atomik test the efficacy of the water plates and is there testing data available?
Why should the public be the guinea pig to find out results if they are effective and useful? What do they (Atomik & MaxAmps) know that you or I missed?
I find this slightly humorous:
This system offer lower temps and higher performance in the Traxxas Spartan
We all know how the Spartan started out, motors and esc's burning up. Before they hit the stores I predicted that their original system would melt down and I was right. I'm not right about everything, hell, I'm wrong a lot! Lets see how this stuff plays out.
Max Amps also states that you will get 26 minutes run time in a Spartan with these 6500 cells in series for 14.8v nominal. I think that's maxing out at 35 amps for 24 minutes by some quick math in my head but, again, I can be wrong.
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