R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 12-16-2007, 10:56 AM   #106
Tech Fanatic
 
darnold's Avatar
 
Join Date: Feb 2002
Location: Bolingbrook, IL
Posts: 940
Trader Rating: 2 (100%+)
Default

So if I get this (and I probably don't),
the advantages of Lipo's are:
-More runs per charge.
-Greater cycle life.
-Less Maintenance.
-Flatter Discharge Curve.
-Little to no Self Dishcarge.
-Lower Long term costs.
-Potentially safer than NiMh's.

The advantages of NiMh's are:
-Fit all classes of cars.
-Provide better weight distribution for better/proper weight transfer as intended by car designs (although some Lipo's are starting to address this).
-Initial cost are cheaper.
-All racers currently have chargers that will charge them.
-Greater overall racing performance (currently).
---------------------------------
The disadvantages of Lipo's are:
-They can go out of balance (even with a balancer which will eventually prohibit them from taking a charge, then a whole new pack is needed instead of tearing down cells and re-matching).

-Lipo cutoff voltages for safety and durability create problems with knowing when a pack is about to "dump". I've seen this happen during club races.

-They cost more to replace per pack (don't just compare to the premium NiMh prices as a budget racer will use budget packs if need be).

-Safety Hazard Considerations.
-The matching process WILL become the norm and drive up the prices.
-They don't fit every class of car.
-They still present weight distribution and CG issues.
-Need new charging equipment (yes there are some $30+ charger/balancers out there but they are still additional purchases).
-Voltages/cell present unique challenges for some predominant/established classes.
-They take longer to charge than NiMh if I am not mistaken, this usually means that they will need to be charged before arrival at the track (and necessitate more packs in order to always have one ready for use).

The disadvantages of NiMh's are:
-Fewer cycles.
-More maintenance .
-Safety Hazard Considerations.
-They go out of "balance" necessitating performance tracking (cycling on a CE 30-35 or Futaba, etc. which consequently further reduces their cycle life).
-They require pack tear downs and rematching to maximize investments.
-Future durability is a concern as performance increases.
-Increased long term cost due to less cycle life and durability issues.
-Takes up more pit/storage space.
-Fewer runs per charge.
-----------------------------
Summary:
Lipo's = less maintenance but more hassles (other issues to contend with).
NiMh = More maintenance (a pain) but fewer hassles (other issues to contend with).

What I can't quite get my head around is why people (not all) who run Lipo's feel and express such a profound need to force people who don't to run them? Why is there so much controversy, especially since it seems that many tracks allow Lipo's to run? They both seem to be co-existing on the club level and the general hobby arena is not affected. Is it really that disdainful to some people who run Lipo's that everyone else isn't running them? Immediate acclimation with technology is not and automatic mandate that must be blindly adhered to (or it makes you "inferior"). In fact, immediate embracing of technology can actually retard progress, and it must be remembered that NiMh technology is moving forward.

What we are really talking about are two different technology paths, NOT one technology path with NiMh's at one point and Lipo's further along on the same path. Thus the argument seems to center on WHICH technology path is better for the racer? Of course if the general or "real" market dynamics for rechargeable batteries were thrown into this debate it would really make things interesting as you would have to consider what the needs are for full size cars (think zero emissions), hand tools and portable devices.

RC racing has certain "needs" that must be addressed in order to make it a reality. Lower maintenance is NOT one of the "needs" but it DOES make it more appealing.

Having: 1. cars "drive" well, 2. not requiring large investments/re-investments, and 3. not radically transforming established classes thereby effecting racers enjoyment and desire to participate are all major "needs".

I would bet that these are at least part of the dilemma that IFMAR, ROAR, EFRA, and other race sanctioning bodies around the world are contending with and why it is taking them so long to address this subject.

It would not surprise me if they eventually have to create a "phase-in" strategy after researching probable future technologies and selecting what, when, and how these will be incorporated into the industry and racing scene.

This means that they will have to have some vision about what will be best for both the hobby and the racing scene and not simply try to cater to either one alone, and THAT is the issue (IMHOP).
__________________
Team Top Racing USA,Team MaClan ESC, Pro One Tires, Hot Race Tires
darnold is offline   Reply With Quote
Old 12-16-2007, 11:34 AM   #107
Tech Master
 
PitNamedGordie's Avatar
 
Join Date: Nov 2003
Location: Highwood, IL
Posts: 1,789
Trader Rating: 8 (100%+)
Send a message via AIM to PitNamedGordie Send a message via Yahoo to PitNamedGordie
Default

Quote:
Originally Posted by darnold View Post
So if I get this (and I probably don't),
the advantages of Lipo's are:
-More runs per charge.
-Greater cycle life.
-Less Maintenance.
-Flatter Discharge Curve.
-Little to no Self Dishcarge.
-Lower Long term costs.
-Potentially safer than NiMh's.

The advantages of NiMh's are:
-Fit all classes of cars.
-Provide better weight distribution for better/proper weight transfer as intended by car designs (although some Lipo's are starting to address this).
-Initial cost are cheaper.
-All racers currently have chargers that will charge them.
-Greater overall racing performance (currently).
---------------------------------
The disadvantages of Lipo's are:
-They can go out of balance (even with a balancer which will eventually prohibit them from taking a charge, then a whole new pack is needed instead of tearing down cells and re-matching).

-Lipo cutoff voltages for safety and durability create problems with knowing when a pack is about to "dump". I've seen this happen during club races.

-They cost more to replace per pack (don't just compare to the premium NiMh prices as a budget racer will use budget packs if need be).

-Safety Hazard Considerations.
-The matching process WILL become the norm and drive up the prices.
-They don't fit every class of car.
-They still present weight distribution and CG issues.
-Need new charging equipment (yes there are some $30+ charger/balancers out there but they are still additional purchases).
-Voltages/cell present unique challenges for some predominant/established classes.
-They take longer to charge than NiMh if I am not mistaken, this usually means that they will need to be charged before arrival at the track (and necessitate more packs in order to always have one ready for use).

The disadvantages of NiMh's are:
-Fewer cycles.
-More maintenance .
-Safety Hazard Considerations.
-They go out of "balance" necessitating performance tracking (cycling on a CE 30-35 or Futaba, etc. which consequently further reduces their cycle life).
-They require pack tear downs and rematching to maximize investments.
-Future durability is a concern as performance increases.
-Increased long term cost due to less cycle life and durability issues.
-Takes up more pit/storage space.
-Fewer runs per charge.
-----------------------------
Summary:
Lipo's = less maintenance but more hassles (other issues to contend with).
NiMh = More maintenance (a pain) but fewer hassles (other issues to contend with).

What I can't quite get my head around is why people (not all) who run Lipo's feel and express such a profound need to force people who don't to run them? Why is there so much controversy, especially since it seems that many tracks allow Lipo's to run? They both seem to be co-existing on the club level and the general hobby arena is not affected. Is it really that disdainful to some people who run Lipo's that everyone else isn't running them? Immediate acclimation with technology is not and automatic mandate that must be blindly adhered to (or it makes you "inferior"). In fact, immediate embracing of technology can actually retard progress, and it must be remembered that NiMh technology is moving forward.

What we are really talking about are two different technology paths, NOT one technology path with NiMh's at one point and Lipo's further along on the same path. Thus the argument seems to center on WHICH technology path is better for the racer? Of course if the general or "real" market dynamics for rechargeable batteries were thrown into this debate it would really make things interesting as you would have to consider what the needs are for full size cars (think zero emissions), hand tools and portable devices.

RC racing has certain "needs" that must be addressed in order to make it a reality. Lower maintenance is NOT one of the "needs" but it DOES make it more appealing.

Having: 1. cars "drive" well, 2. not requiring large investments/re-investments, and 3. not radically transforming established classes thereby effecting racers enjoyment and desire to participate are all major "needs".

I would bet that these are at least part of the dilemma that IFMAR, ROAR, EFRA, and other race sanctioning bodies around the world are contending with and why it is taking them so long to address this subject.

It would not surprise me if they eventually have to create a "phase-in" strategy after researching probable future technologies and selecting what, when, and how these will be incorporated into the industry and racing scene.

This means that they will have to have some vision about what will be best for both the hobby and the racing scene and not simply try to cater to either one alone, and THAT is the issue (IMHOP).
You make some nice points. The only thing that I would say is that lipos take less time to charge after use. I have found that after running 7-8 minutes in a practice session I can recharge my packs in 15 minutes or less. That is the real advantage I see. I can get away with bringing one pack on a practice day (however I have 2...no waiting on packs to charge at all).

But interestingly enough I am considering going back to NiMH because of the car balance issues. Trying to find the best way to balance my car is a hassle. Just recently I shorted one of my Orion 4800. Now I have a choice to make...pay $135 for another 4800 or buy 2-3 NiMH packs to go with my 3 IB4200s I still have. I still have my NiMH equipment so that won't be an issue. But with some of the cheaper lipos out (Trinity 4500 for $80) I am not sure which way to go. And actually the NiMH will be less of a hassle at this point...
__________________
☆ The Track @ Harbor Hobbies ☆ www.harbor-hobby.net ☆
PitNamedGordie is offline   Reply With Quote
Old 12-16-2007, 12:09 PM   #108
Tech Fanatic
 
darnold's Avatar
 
Join Date: Feb 2002
Location: Bolingbrook, IL
Posts: 940
Trader Rating: 2 (100%+)
Default

Thanks for the information regarding charging at the track. So basically all a racer would have to do is "re-peak" after every run if I understand you correctly.

One thing to think about is that the capacity of Lipo's are directly related to heat. Thus charging a lipo pack up right after a high drain application (run) is actually damaging to battery capacity due to the heat generated from the run. This is why lower charge rates are also recommended for Lipo's (even for high "C" batteries) from what I have been able to research. Also, Lipo's actually do have self discharge, it is just lower than NiMh's and they are also adversely affected by high drain applications even if they are rated for it just as NiMh's are.
__________________
Team Top Racing USA,Team MaClan ESC, Pro One Tires, Hot Race Tires
darnold is offline   Reply With Quote
Old 12-16-2007, 12:59 PM   #109
Tech Elite
 
dawgmeat's Avatar
 
Join Date: Apr 2004
Location: Jacksonville, FL
Posts: 2,505
Trader Rating: 6 (100%+)
Default

Hey Danny thanks for Hijackin' this thread and all the bahbahbah about how your lipo goin' to be all that, when racers had to to deal with youe PURE SH!T cells....you know the one that you could buy with bad cell that last about 2 weeks YOU WERE NOWHERE IS TO SEEN OR HEARD FROM ON rctech, I just don't believe you, this kinda of reminds when everytime Orion had a new thread you would just comeover and take it over with your SMC is better than Orion mess


You couldn't give SMC cells away 2 months ago you nowhere to be found welcome back
dawgmeat is offline   Reply With Quote
Old 12-16-2007, 02:22 PM   #110
Tech Elite
 
bvoltz's Avatar
 
Join Date: Jun 2005
Location: Bedtime with Teddi
Posts: 3,635
Trader Rating: 44 (100%+)
Default

Quote:
Originally Posted by darnold View Post
What I can't quite get my head around is why people (not all) who run Lipo's feel and express such a profound need to force people who don't to run them? Why is there so much controversy, especially since it seems that many tracks allow Lipo's to run? They both seem to be co-existing on the club level and the general hobby arena is not affected. Is it really that disdainful to some people who run Lipo's that everyone else isn't running them? Immediate acclimation with technology is not and automatic mandate that must be blindly adhered to (or it makes you "inferior"). In fact, immediate embracing of technology can actually retard progress, and it must be remembered that NiMh technology is moving forward.

I really do not think this the case... I do think the LiPo people would like them ok to run at all events... maybe I'm missing something here

I agree, run them together... You run what you want...
__________________
Wheeling an Xray T4 and T4 14 using a Ko Propo, powered by EA motors and Speed Passion Speedo, paid for by my wife.

Digi3Dworks - 3D printing for the medical Field.
bvoltz is offline   Reply With Quote
Old 12-16-2007, 02:26 PM   #111
Tech Apprentice
 
Join Date: Dec 2007
Posts: 89
Default

have any one noticed that non of the pros,factory sponsored or company sponsored racers will input thier opinion and what they think,when it come to lypo or brushless,with all this discussion.why is that?
sure thier opinions will be respected,they are the leaders.
all the a-main drivers in big racers should say somthing as well as the b- main drivers.
and plz dont wanna hear comments like:they dont have time or no internet connection
trackpower is offline   Reply With Quote
Old 12-16-2007, 02:30 PM   #112
Tech Apprentice
 
Join Date: Dec 2007
Posts: 89
Default

Quote:
Originally Posted by bvoltz View Post
I really do not think this the case... I do think the LiPo people would like them ok to run at all events... maybe I'm missing something here

I agree, run them together... You run what you want...
i agree,if they can run them in big events,we wouldnt have this discussion.
proplem its not up to the racer to decide,its up to roar
trackpower is offline   Reply With Quote
Old 12-16-2007, 02:50 PM   #113
Tech Master
 
billjacobs's Avatar
 
Join Date: Sep 2004
Location: Rockville, MD
Posts: 1,264
Trader Rating: 55 (100%+)
Default thoughts

We are running sub cells because:
1) too much equipment designed for sub-c would be worthless
2) matchers wouldn't make money
3) if everything went to lipo, all current chassis and 1/12th scale (except losi and team magic) would be obsolete
4) all currently battery sponsored racers would have to buy new packs and most would have to buy their own packs.

I can care less what anybody runs, but, I just balanced an xray t2 with bmi asphault chassis and micro electronics (tekin fx pro, spektrum micro receiver, futaba 9550 servo, brushed motor) and an orion 3200 lipo and my car rtr weighed 47.5 ounces (rubber tires.) So to use my lipo pack in racing, I have to add a little over 7 ounces more weight to the car (I already added 4.5 ounces to balance the car) which would result in a slower car that used more tire and made the motor work harder.

This is why those of us who use lipo want everyone else to run it, not because we care what others run, but so that the rules will be changed and we can run lighter cars. People who use nimh don't see the argument from this point of view, they just think that others want them to give up their nimh packs.
billjacobs is offline   Reply With Quote
Old 12-16-2007, 02:55 PM   #114
Tech Apprentice
 
Join Date: Dec 2007
Posts: 89
Default

Quote:
Originally Posted by billjacobs View Post
We are running sub cells because:
1) too much equipment designed for sub-c would be worthless
2) matchers wouldn't make money
3) if everything went to lipo, all current chassis and 1/12th scale (except losi and team magic) would be obsolete
4) all currently battery sponsored racers would have to buy new packs and most would have to buy their own packs.

I can care less what anybody runs, but, I just balanced an xray t2 with bmi asphault chassis and micro electronics (tekin fx pro, spektrum micro receiver, futaba 9550 servo, brushed motor) and an orion 3200 lipo and my car rtr weighed 47.5 ounces (rubber tires.) So to use my lipo pack in racing, I have to add a little over 7 ounces more weight to the car (I already added 4.5 ounces to balance the car) which would result in a slower car that used more tire and made the motor work harder.

This is why those of us who use lipo want everyone else to run it, not because we care what others run, but so that the rules will be changed and we can run lighter cars. People who use nimh don't see the argument from this point of view, they just think that others want them to give up their nimh packs.
v good opinion
trackpower is offline   Reply With Quote
Old 12-16-2007, 03:15 PM   #115
Suspended
 
Join Date: Mar 2003
Location: Back That Thang Up!
Posts: 3,468
Trader Rating: 11 (100%+)
Default

Quote:
Originally Posted by trackpower View Post
have any one noticed that non of the pros,factory sponsored or company sponsored racers will input thier opinion and what they think,when it come to lypo or brushless,with all this discussion.why is that?
sure thier opinions will be respected,they are the leaders.
all the a-main drivers in big racers should say somthing as well as the b- main drivers.
and plz dont wanna hear comments like:they dont have time or no internet connection
Their boses told them to shutup or lose their coveted sponsorship.
403forbidden is offline   Reply With Quote
Old 12-16-2007, 03:17 PM   #116
Tech Elite
 
Leodis's Avatar
 
Join Date: Feb 2007
Posts: 2,058
Trader Rating: 16 (100%+)
Default

Quote:
Originally Posted by trackpower View Post
have any one noticed that non of the pros,factory sponsored or company sponsored racers will input thier opinion and what they think,when it come to lypo or brushless,with all this discussion.why is that?
I've talked to and overheard a handful of factory and sponsored drivers discussing LiPo and they all think it's the future, but some of them are pushing for its early acceptance while others are waiting until LiPo is legal at the big races. Don't expect them to come on rctech and make their opinions known because this NIMH vs. LiPo debate is like the "Abortion" issue of rctech. Regardless of their opinons, they'd still end up losing.
Leodis is offline   Reply With Quote
Old 12-16-2007, 03:39 PM   #117
Tech Fanatic
 
darnold's Avatar
 
Join Date: Feb 2002
Location: Bolingbrook, IL
Posts: 940
Trader Rating: 2 (100%+)
Default

BillJacobs- Thank you. That answers it for me. Basically lipo racers according to your post want everyone else to change for them. No compromise, no co-existence of technologies, no planned "phase-in" periods, and thus the huge battles.

So the lipo racers (according to your post) have to get everyone else to change over to them so that they can get the "full" benefit of the lighter lipo's. So really, you DO care about what others run because you want them to run what you run so that you get what you want.

You would have to add weight to get the car to transfer weight properly to handle well ANYWAY because the cars are DESIGNED as such.

In your scenario everyone would have to do a lot more after such a weight reduction rule was in place and to be honest, such a weight reduction rule would only have one purpose: To eradicate NiMh technology from racing (while forcing everyone to design and buy new cars, form new classes and eliminate some established, thriving racing formats).
All because some people want it.

The issue may not be what the future technology path will be but instead seems to be more about how to phase that technology path in so that you don't loose the industry.

Some industry insiders (the business side of things) have already said that our switch to BL seems to be correlated with a loss in racing numbers. They have said that it appears that for every 1 person we gained for BL 2 are staying home and not racing anymore, even on the club level (nationally that is, your local scene may vary). Now BL is less of a transition than Lipo would be and you still think it has to happen now? You really think this is going to make everything better?

This probably highlights the underlying issue which is that a cohesive vision for the industry is still being worked on by the org's and manufacturers. Until that happens we are left with the crowd mentality of whose followers can make the biggest fuss to get what they want in spite of everyone else.
__________________
Team Top Racing USA,Team MaClan ESC, Pro One Tires, Hot Race Tires
darnold is offline   Reply With Quote
Old 12-16-2007, 03:54 PM   #118
Tech Apprentice
 
Join Date: Dec 2007
Posts: 89
Default

ok mr darnold,its clear which side of the pond u are on,if though u are not saying it direct.
its cool,but before my next post i just wanna ask,whats the idea behind weight limit rule in sedans at least,why the restrictions,its not like we gonna take out the tires to make it lighter(really i dont know),even whats wrong with trying to make chassis as light as possible?thx
trackpower is offline   Reply With Quote
Old 12-16-2007, 03:56 PM   #119
PDM
Tech Adept
 
Join Date: Sep 2007
Posts: 184
Default

Quote:
Originally Posted by C_O_jones View Post
...and with lipo and brushless in a development stage...
Here is the answer why people still run sub-c NiMh cells.

Some people think because they never heard about it, it does not exist.

Development stage? for lipo and brushless? c'mon my friend.

They are on the market for 6 years, at least. Brushless much more than that.

In a way you are right, some brands are in development stage in brushless, all that still need sensors, in an year they will change for sensorless as other have done before. But it is not brushless that are in development, those brands you know are...
PDM is offline   Reply With Quote
Old 12-16-2007, 05:40 PM   #120
Tech Master
 
billjacobs's Avatar
 
Join Date: Sep 2004
Location: Rockville, MD
Posts: 1,264
Trader Rating: 55 (100%+)
Default darnold

darnold- Wow, I never knew I spoke for all lipo advocates. Was I elected, drafted?

Which industry insiders have said that BL has caused a decline in the number of racers? The only way that BL could do this is if the brushed racers who were too happy to work on motors, and spend lots of money on brushed motors suddenly found out that the big bad brushless motors were faster than their brushed motors. I could have told you that brushless is faster, more efficient, and more consistent before brushless motors came out. At tracks in my area, attendance is up because of brushless.

Brushless is cheaper, requires less work, and is much more fun for the average racer. If you don't believe me, do the following: imagine a brushless system is $100. If that were the case, would anyone still run brushed. Now take the novak xbr system at $169. Is the $69 worth an end to working on motors, cutting comms, changing brushes, oh.... and replacing motors every few months?

Of course industry insiders who tune motors and sell brushes see their incomes in jeopardy.

Now back to LIPO. On the one hand you have nimh which requires maintenance equipment and 2 or 3 times the number of packs as LIPO to race. Nimh is the established technology, and is the basis for most r/c car designs and layouts (except those cars that have the weight down the center, or that have the weight across the chassis (ta04, etc.)) Nimh also requires upkeep to stay race-worthy.

On the other hand you have the relative upstart LIPO which lets you race with 1 pack (i've done it, simply run and recharge,) requires inexpensive chargers, and requires no other equipment, but costs 30-40% more than nimh, and lasts at least 5 times as long. Oh, and it's also 1/2 the weight which translates into less tire wear, less motor wear, fewer broken parts, etc.

Advocates of nimh over lipo say that nimh was here first, so lipo has to conform to nimh in terms of weight, size, shape, etc. That is like saying motor boats should all have sails because sail power was invented first. But 1 thing has changed, when LIPO first came out, the big furor was that LIPO was faster, since this has proven to be false, nimh advocates try to find anything else to hamstring lipo and give nimh the advantage, which is where the weight issue comes in. Ask yourself this, does making the car heavier by 7 ounces have any useful purpose other than to conform to the roar weight limits? Does anyone really think that nimh is the future? Then why are people fighting so hard to hold onto it?

I never said I want to have all of the advantages. I just said that trying to add 7 ounces to a car that is already balanced is silly.
billjacobs is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Anyone running Orion 4500mh cells? Loverc Electric Off-Road 0 12-22-2007 10:25 AM
running too rich or running to lean bumm_off_street Nitro On-Road 7 03-29-2006 08:28 PM
XRAY T1FK - RC12L3 - Serpent 710 - Surge Batteries (4-cells & 6-cells) and more XrayRacer R/C Items: For Sale/Trade 24 03-31-2005 03:19 PM
Anybody running the new 3600 cells yet? Bflat Electric On-Road 74 07-19-2004 07:01 PM
Esc: will running more cells hurt? huasze Singapore R/C Racers 9 02-10-2003 04:49 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 03:25 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net