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Old 08-09-2008, 11:07 PM   #1
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Default Lipo confusion

I've been reading many threads about Lipos and I'm a bit confused when it comes to Lipos being purchased for racing. Typically racers want the best motors and batteries as speed is normally part of racing. When it comes to Lipos they seem to not understand that Lipos are just like any other battery and there are differences between the various packs out on the market.

When purchasing sub-c cells racers want to buy the best possible cells with the lowest IR and highest average voltage. When it comes to Lipos many seem to be lost with all the different packs available.

Here is what has an effect on a Lipo packs performance. Capacity , C rate and the materials used to build the packs make for differences in performance.

Capacity: Higher capacity means the cells will be bigger which will lower the IR and increase the average voltage.

C rate: A higher C rate will mean the pack will have lower IR and higher average voltage. The pack will also recover faster from high amp loads.

Materials: The use of premium grade materials and the way the packs are assembled makes for lower IR and higher average voltage.

Packs with bigger capacity , higher C rate and better materials will cost more.


If you look at our lineup of Lipos which include a 3200/28C , 4000/28C and a 5000/28C the 3200 has higher IR than the 4000 and the 5000 has lower IR than the 4000.


Since Lipo manufacturers use different methods to test C rate and capacity you should only compare packs from the same manufacturer. An example of this would be a company who has a 20 and 30C 5000 pack. The 30C pack would be better than the 20C. That being said a 20C/5000 from one company can't be compared to another company who has a 20C/5000. The only way to compare them would be to cycle them and measure the IR , average voltage and capacity or track testing them to see which pack is faster.


I hope that this can help reduce some of the confusion about Lipos used for racing.
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Old 08-10-2008, 12:48 AM   #2
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Originally Posted by Danny/SMC View Post
I hope that this can help reduce some of the confusion about Lipos used for racing.
What kind of motors and racing does it make a difference what type of 7.4volt Lipo battery I use?

I'm assuming here and please correct me:

Any motor near a stock motor, like a 21.5 brushless or a 17.5 or brushed 27T a specific Lipo can make a difference in lap times

Running a 19 Turn, or a 13.5 what specific Lipo you run might make a difference in lap times to put you ahead of other racers.

Anything under a 19 turned brushed or a 13.5 brushless a battery isn't going to make a difference?

When I say "make a difference" I mean an intermediate racer who isn't getting marshalled much and can run a relatively good line and can tune their vehicle to be competive with the majority of racers at their club.

I don't mean:

Any of the top 200 racers in the US.
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Old 08-10-2008, 10:02 AM   #3
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In the limited motor classes it's more important to have the better performing pack. In mod cars are already to fast and you could always use a faster motor so it isn't as critical but a higher C rate pack may hold up better to the higher amp rates being generated by mod motors.
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Old 08-10-2008, 10:28 AM   #4
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Danny/SMC

I think something that too often gets misconstrued in racing is that everyone wants to go FASTER.

I personally believe that's a MYTH...and here's what I mean.

MFG's are always looking to make products that go faster than their last product. But RACERs are trying to go FASTER with the equipment THEY already HAVE.

Every time a NEW/FASTER product comes out EVERYBODY goes faster, but for most...it's BACK to the DRAWING BOARD trying to figure out HOW TO GET THE MOST out of WHAT THEY HAVE.

The problem w/ the part of the MFG's making stuff faster for us is, it's BOLT ON SPEED and EVERYBODY gets it...which generally ends up making EVERYONE too fast (If they want FAST - RUN Modified)

Then things have to be changed to SLOW people down...which creates ALL new products, classes, etc. Which causes some people to get frustrated and leave this hobby.

(Example: Oval Pan Cars going to 4 cell roughly 11 years ago, the PUSH to take TC's to 4 and 5 cell...etc.)

As a racer, I want to FINE TUNE my setup every time I go to a track...and I want that equipment to STAY THE SAME for a fairly long period of time...so I know EXACTLY how much better I've made MY setups.

NEW/FASTER/BETTER products don't make for BETTER racing, it just makes for MORE Expensive Racing.

Now with MANY directions of racing going to LIPO, there has been many calls for LIMITING what type and size battery can be used.

Do you think that is because "Racer's Want to Go Faster?" No, it's because RACER's get tired of CHASING PRODUCTS...instead of focusing on RACING.

I was instrumental in helping create the 17.5 and 21.5 Brushless Classes...in an effort to SLOW DOWN Brushless racing, cause it was TOO FAST for most people on MOST tracks.

I started by only focusing on OVAL (Cause that's MY passion), but quickly saw that these slower motors worked GREAT in both Off-Road and On-Road...so I worked on pushing them into those markets as well. NOT cause racer's wanted to GO FASTER, but because there was a NEED for something SLOWER.

The problems we've run into in OVAL racing is we were trying to replace the EVER CHANGING Round Cells, AND move back to a common voltage shared w/ other forms of racing (Instead of 4 cell).

These two motor options have proved to be almost still TOO FAST w/ LIPO for a lot of racers, and we're still working/looking for one more SLOWER Brushless/LIPO option.

IMHO - RACING is NOT about SPEED, it's about BEATING the OTHER DRIVER.

There are plenty of OPTIONS for the SPEED at which you want to compete - and with B/L and LIPO, Lack of Speed is NOT an issue.

(NOTE: These are MY opinions, based on what I've seen,heard, and experienced over the past 23+ years in this Hobby/Sport)

Joe Myers
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Central Coast R/C Racing
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Old 08-10-2008, 10:40 AM   #5
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I do believe cars need to be slowed down as speeds are a bit out of control. This is where BL motors come into play as you can go to slower motors to slow the cars down.

As far as Lipos go there is a maximum size rule set by ROAR plus they do safety tests before they approve a pack which is a great thing.

It's pretty much impossible to control other aspects of Lipos just like it's pretty hard to make rules to keep sub-c cell makers from making better cells. As long as the cells/packs are within the size rules you can't really limit anything else.

As a track owner or race director you can always set a battery rule where everyone runs one type of pack. If racers feel this is the way to go then they will race in this class.
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Old 08-10-2008, 10:50 AM   #6
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Quote:
As a track owner or race director you can always set a battery rule where everyone runs one type of pack. If racers feel this is the way to go then they will race in this class.
That's exactly what we did when we created the classes for the 17.5 and 21.5 motors. We started w/ ONE Mfg...for ONE year, and hoped other MFG's would build packs that would prove to be compatible w/ that pack.

Several have, but now we've got your 3200 LIPO which by all accounts is by far ABOVE those others...so instead of being able to OPEN the classes up and continue to be unified across the country we're going to see division again, or a different company (SMC) become the "EXCLUSIVE".

You refer to ROAR and ROAR's RULES, the problem is w/ ROAR is they do NOT have "Brand Exclusitivity" options. So this will let a MIXED BAG of "UnEqual" products all become legalized, because they don't yet have a GRASP or a BLUEPRINT for either LIPO batteries or BRUSHLESS MOTORS.
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Old 08-10-2008, 11:25 AM   #7
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Why would we build an inferior pack just because that is what others are doing ? Even if we would make a 20C/3200 it would be better than what is currently out on the market. The materials used by our supplier is premium grade materials.

The fact is 80% of the Lipos out on the market have inflated C rates or capacity. This is why we cycle our packs and print the numbers on the packaging as our goal is to supply a pack with true C rate and true capacity.


If you feel were trying to screw up the market just ban our packs from your organisation. We have gotten great feedback from others as we can guarantee our 3200 pack to stay the same for atleast 2 years so many tracks will be adopting it. This is no different than what you did by only allowing the Orion pack which is now discontinued.
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Old 08-10-2008, 11:36 AM   #8
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I think its long overdue that rc mags such as XTREME RC start to benchmark our new technologys.

Just as they did with the X-dyno for nitro engines its high time we started to see a data base of info with benchmarks for both batteries(lipo and nihm) and brushless motors.

If such benchmarks where set. Turbo charger set at profile XYZ charged in a room at 70F at 40% humidity ect ect type bs. Everytime a new pack drops they review the pack, and run the benchmark... If the PC GAMER guys can benchmark 200 video cards a year surely we can get numbers on all the available lipos out there...

It would be very intresting to see how things really stack up.... Im sure SMC will at or near the top...

We are right around the corner from seeing matched lipos eh danny?
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Old 08-10-2008, 11:43 AM   #9
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Quote:
Originally Posted by SWTour View Post
The problems we've run into in OVAL racing is we were trying to replace the EVER CHANGING Round Cells, AND move back to a common voltage shared w/ other forms of racing (Instead of 4 cell).

These two motor options have proved to be almost still TOO FAST w/ LIPO for a lot of racers, and we're still working/looking for one more SLOWER Brushless/LIPO option.
The answer to your problem is relatively simple: smaller rotors. More turns isn't the answer. Allow 2s lipos, but put in a rule that requires a small rotor. All other ROAR motor rule specs still apply. Shrinking rotor size will get the motor RPM back up, and kill motor efficiency. It's also a cheap and easy retrofit for both manufacturers (only one new part) and existing owners ($30) to do.
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Old 08-10-2008, 11:48 AM   #10
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Originally Posted by Joel Lagace View Post
We are right around the corner from seeing matched lipos eh danny?
Lipos have been matched since they came onto the airplane scene in 2003. Manufacturers that don't match simply don't think there is a reason to. Either way, you won't see the mythic and expensive "matcher's touch" playing a performance role in the lipo market.
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Old 08-10-2008, 11:52 AM   #11
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The problem with having magazines doing a test on packs is that they tend to not want to upset advertisers. How many times have a you seen a shutout between different products only to have a tie or good things to say about both products.

We have tested many different Lipos to see what is currently available and we send them back to our supplier to have C rate testing done on them. I think there should be some testing done to show the consumer what they are paying for. This is why we print the specs of each pack on our packaging. We could gladly do the testing but then the results could be argued as it would show our packs have true C rate and capacity and they also have better specs. We would really support an independent test.


Our Lipos are already matched by our supplier and other manufacturers do this as well.
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Old 08-10-2008, 12:02 PM   #12
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Magazines are dead, mostly. What this hobby needs is a proper blog that does this sort of thing, and doesn't have to worry so much about appeasing advertisers since it's practically free to run. If I had more time, I'd do it myself. Something kind of like what Oople does, but with electronics, and more on-road centric.
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Old 08-10-2008, 12:14 PM   #13
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As we have nothing to fear about having our Lipos tested as we already know how they stack up against what is currently available were looking into setting up a Lipo test that we would have someone neutral do the testing. The problem is testing C rate is very hard to do as it requires allot of power dissipation. There is equipment out there that can do this but it's fairly expensive.
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Old 08-10-2008, 12:33 PM   #14
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That's exactly what we did when we created the classes for the 17.5 and 21.5 motors. We started w/ ONE Mfg...for ONE year, and hoped other MFG's would build packs that would prove to be compatible w/ that pack.

Several have, but now we've got your 3200 LIPO which by all accounts is by far ABOVE those others...so instead of being able to OPEN the classes up and continue to be unified across the country we're going to see division again, or a different company (SMC) become the "EXCLUSIVE".

You refer to ROAR and ROAR's RULES, the problem is w/ ROAR is they do NOT have "Brand Exclusitivity" options. So this will let a MIXED BAG of "UnEqual" products all become legalized, because they don't yet have a GRASP or a BLUEPRINT for either LIPO batteries or BRUSHLESS MOTORS.
There are two sides to every argument. As a race director, you want racing as equal as possible so everyone keeps coming back and having fun. You do not care what brand of battery is run, as long as it is close to your benchmark.
As a manufacturer, we have the same goals. We want racers to have fun and continue racing. Our future depends on it. The difference is that we DO care what battery is run. We want it to be SMC. The only way to ensure that, is to build a better battery that still conforms to the rules. We are not ruining the market. We are just maximizing the technology available. We offer legitimate C rated packs that perform as advertised. It is not our fault that other companies advertise inflated C rates. Maybe someone should get on them for misleading the public.
It is not ROAR's job to worry about "unequal products" becoming legalized. There always have and always will be some products that outperform other products. It is not fair to any manufacturer to exclude them from the rules simply because their products are "better". That is absurd.
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Old 08-10-2008, 01:05 PM   #15
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There are two sides to every argument. As a race director, you want racing as equal as possible so everyone keeps coming back and having fun. You do not care what brand of battery is run, as long as it is close to your benchmark.
Jack,

I'm a RACER First - a GRASS ROOTS, SPORTSMAN LEVEL (Non-Sponsored, Non-Factory) Racer. Which is how it's been MOST of the 23 years I've been racing.

As a RACER, I'm about RACING other RACERS...NOT Chasing the NEWEST/LATEST "Product"

I'm a race director/promoter 2nd..and that ONLY happened because NOBODY else did, or was going to DO IT - and I refused to let R/C OVAL Racing DIE on the West Coast.

As a RACER - one of the MOST heard complaints I've ever heard (FROM OTHER RACERS) was the "Battery of the Week" and/or "Motor of the Week" and I have watched over the years literally 100's or racers LEAVE this hobby.

As a RACE Director/Promoter...it's funny, but the complaints heard are VERY SIMILAR - plus the complaints about the "SPONSORED ONLY" guys product availability.

As far as ORION and THEIR LIPOS - and/or MISLEADING ANYONE...

ORION was Sought Out - they did NOT come trying to PUSH their stuff into "Our" market.
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