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-   -   Lipos vs NiMH......Nicads....Alkalines (https://www.rctech.net/forum/electric-road/109582-lipos-vs-nimh-nicads-alkalines.html)

Ducati-Rider 04-10-2006 10:18 AM

Lipos vs NiMH......Nicads....Alkalines
 
If Lipo packs are the next quantum leap in stored energy technology and brushless are the next jump from brushed, then what drives the acceptance of LIPOs for the common man?

I have come to the conclusion that all batteries are dangerous and can start fires, just like bullets kill innocent people and bad drivers cause wrecks.

It also seems that holding back LIPOs from the market and normalized usage may infact be a ploy by battery matchers (suppliers) and those in the industry who won't make as much money if LIPOs last longer and eventually are cheaper per car run cycle over their lifetime.

Same is true for brushless motors - just look at the cottage industry of rebuilders and tools, brushes, zapping and what other wet nursing brushed motors require to go fast.

My question to you guys is What does it take to get LPOS or the next generation of batteries accepted, and who controls the distribution and approval of the next wave?

Is it the end customers - you and I
or
The industry, retailers, repackagers and the business drivers?

What do you think?
What do we need to do to make the jump?

And please don't give me excuse that LIPOs will burn your house down if poked with a screwdriver!

Rysuleod 04-10-2006 11:10 AM

Don't overlook the fact that all electric cars are designed for sub-c cells. No one is producing a car balanced for lipos since there isn't really a standard lipo size.

With sub-c battery capacity going up and up, it's really hard to sell people on lipos other than the maintenance.

I'm not an electrical engineer that knows how much difference this makes but lipos are 7.4V instead of 7.2 (1.2x6) for sub-c cells.

Every charger on the market for sub-c cells would have to be redesigned or scrapped. Not to mention all the battery matchers that would be put out of business. It would pretty much require a complete focus change in the r/c industry. That focus change would likely wipe out all the small companies that could not afford to adapt. Many new companies would emerge, but the point is.. those getting killed off would probably not be receptive ( and for good reason) to the technology change.

I doubt ROAR has any actual power,but tracks I race at still loosely follow ROAR rules. Until sanctioning bodies approve lipos for major events the sub-c technology will probably not be replaced.

p.s. I only run at the club racing level and I own a scorpion 3200 pack. The punch is awesome, the ability to recharge the same pack is awesome, not having to specially charge or discharge the pack is awesome. I recommend lipos to all lazy racers like myself. :nod:

SlowerOne 04-10-2006 11:52 AM

Things to be sorted out before LiPo can be used...

Safety - a product with flat plates that must not touch each other, placed in an environment where they are vibrated up and down, is not a recipe for safety. Similarly, the huge safety margin in NiMh that means we have precious few accidents is not present in LiPo. Manufacturers may not produce the batteries for RC cars because the consequences are foreseeable, and they may get sued.

Touring Cars - Japan has gone to four-cell, Europe may follow suit, and 12th is already four-cell. The 3.7v LiPo in this application means we have to change all our electronics - speedos, receivers, servos - and that ain't cheap for any driver, let alone manufacturer development costs!

Size of the market - if Touring Car goes four-cell, then that leaves only Off-Road on 6-cell, LiPo's ideal market. And Off-Road isn't big enough to pay back the investment in bringing LiPo to market.

Source of supply - I have no data, but I'm willing to speculate that if LiPo turned up it would be expensive, and the Chinese NiMH manufacturers would still have room to lower prices to keep LiPo out of the market.

Rules - until ROAR, EFRA, JMRCA and IFMAR make rules allowing LiPo, manufacturers have little (or no!) incentive to provide a product. Nobody's holding back from NiMh development, but they have a clear set of rules to aim at. Who'd develop a LiPo system if the rules didn't subsequently allow them to race?

Apart from all the issues above, it is plain sailing to get LiPo into RC! :)

Rick Hohwart 04-10-2006 01:09 PM


Originally Posted by SlowerOne
Safety - a product with flat plates that must not touch each other, placed in an environment where they are vibrated up and down, is not a recipe for safety. Similarly, the huge safety margin in NiMh that means we have precious few accidents is not present in LiPo. Manufacturers may not produce the batteries for RC cars because the consequences are foreseeable, and they may get sued.:)

LiPos are already here! Newer Lipos, like those made by Kokam and used in Team Orion Platinum battery, are safer than ever and no more of a danger than NiMH or NiCd batteries when treated as they are supposed to be treated.


Originally Posted by SlowerOne
Touring Cars - Japan has gone to four-cell, Europe may follow suit, and 12th is already four-cell. The 3.7v LiPo in this application means we have to change all our electronics - speedos, receivers, servos - and that ain't cheap for any driver, let alone manufacturer development costs!

These choices are unfortunate. Electric has taken quite a hit from nitro in terms of popularity. So the solution is to make the cars slower with the same runtime? LiPos, with increased power AND run time are the solution to bring electric racing back the the prominent position it once enjoyed.


Originally Posted by SlowerOne
Size of the market - if Touring Car goes four-cell, then that leaves only Off-Road on 6-cell, LiPo's ideal market. And Off-Road isn't big enough to pay back the investment in bringing LiPo to market.!

Bring LiPos to off-road and it WILL become big enough to justify developement costs. Touring car will simply die off while off-roaders enjoy all the benefits of LiPo technology.


Originally Posted by SlowerOne
Source of supply - I have no data, but I'm willing to speculate that if LiPo turned up it would be expensive, and the Chinese NiMH manufacturers would still have room to lower prices to keep LiPo out of the market.

I had to check the post date to make sure this actually was posted today. LiPo is here for R/C cars. There will never be a NiMH cell that is as efficient, as powerful, as long running, and as long lasting as LiPo. LiPo offers the greates value NOW, and will only become a better value with future development.

[QUOTE=SlowerOne]Rules - until ROAR, EFRA, JMRCA and IFMAR make rules allowing LiPo, manufacturers have little (or no!) incentive to provide a product. Nobody's holding back from NiMh development, but they have a clear set of rules to aim at. Who'd develop a LiPo system if the rules didn't subsequently allow them to race?[/QUOTE}

Consumer demand drives the rules. Most tracks will allow LiPos in modified class. All will have to by the end of the year. Do you actualy think a business can turn away a customer because they want to run a better, more economically viable product? No way! And if they do they are going to send their customers to a competitor who allows them.


Originally Posted by SlowerOne
Apart from all the issues above, it is plain sailing to get LiPo into RC!

Again, LiPos are already here - and here to stay!

linger 04-10-2006 02:02 PM


Originally Posted by SlowerOne
Things to be sorted out before LiPo can be used...

Safety - ...

Touring Cars - Japan has gone to four-cell, Europe may follow suit, and 12th is already four-cell. The 3.7v LiPo in this application means we have to change all our electronics - speedos, receivers, servos - and that ain't cheap for any driver, let alone manufacturer development costs!

Source of supply - I have no data, but I'm willing to speculate that if LiPo turned up it would be expensive, and the Chinese NiMH manufacturers would still have room to lower prices to keep LiPo out of the market.

Regarding Safety - Tamiya USA just finished a 3 hour enduro and LiPo batteries were allowed. Most of the teams ran LiPo after Lipo after Lipo with absolutely no battery problems. Kokam has designed in safety features where the Lipo will create internal open circuits when the battery is punctured or shorted out.

Regarding Touring cars - 4 cell touring car? that already requires a complete overhaul of the touring car chassis and I've seen NONE on the market that are actually raced.

Regarding cost - industry wide surveys have shown NiMh to be rising in cost at a rate of 2-3% a year due to the higher raw material cost of the chemistry. LiPo's have been decreasing in cost at a rate of 12%-15% a year. It will be about 2 years and the cost will be the same.

Regarding lifecycle - don't you hate it when your brand new NiMh loses 30 seconds of runtime after just a few cycles (especially in mod). What's worse is that NiMh seem to loose a bit of punch after less than 10 cycles. Lipos degrade at a much slower rate and they don't require a strict dishcharging regime. Over the life of the battery, LiPO will cost LESS.

The biggest naysayers of Lipo are the people who haven't tried them.

linger 04-10-2006 02:06 PM

One more comment,

At the Tamiya USA 3 hour enduro, we ran all LiPo's for the entire event, but we ran out of charged LiPo's for the last 6 minutes. For the last battery change, we popped in a brand new set of IB3800's that belonged to a team driver. When our driver walked off the stand, he said that the very last battery pack felt flat - at that time, he didn't know that the last pack was NiMh.

Grizzbob 04-10-2006 02:50 PM

As has become obvious, you'll get different responses from different people, but I know for me, 2(& a half) things are what keep me from jumping into LiPo's. 1. Rules, I don't see a reason to spend that much money on new packs when no big races(like Cleveland, the Snowbirds, the Novak USTC or Vegas IIC, for example) will allow them, & 2. Cost. No matter how you slice it, $150 is a LOT of cash for one battery pack(I can easily buy 2 top notch packs from my preferred matchers for less than that) & also(this is the half part) I'd have to buy a new charger that can accomodate LiPo's(& there aren't as many of them as I'd like to see, & none are exactly cheap, & no, Rick, I'm not forgetting Orion's Advantage, nothing against it but my loyalties simply lie elsewhere). All that being said, I do suspect that eventually, they WILL become the norm everywhere, but there's no reason to rush it. I still remember when NiMh's were first talked about(& it was around 1989, believe it or not) but it took another 10 years or so to put out a useable cell, & a couple more before a GOOD raceable cell arrived(& by then it was just beginning to gain acceptance by everyone), so just be patient, it'll happen.... :cool:

pheyhoe 04-10-2006 03:03 PM

So is this thing about not having to discharge them true?

I can remember when NIMH came out they were advertised as not needing to be discharged as they had "No memory effect"

But that didnt last long....

Im all up for LIPO and cant wait until cars, chargers, rules all change to allow :)

Racingbod85 04-10-2006 03:18 PM

Lipos don't need an expensive charger!you can pick up a basic plug and play for £20 or one with 4 lines of data (voltage, amps, time, etc) for £60! :nod:

Safety - a product with flat plates that must not touch each other, placed in an environment where they are vibrated up and down, is not a recipe for safety.

lipos have been in planes for years - wot do you think the vibrations and g-forces are like in them!! :rolleyes:

the voltage isn't the difference between lipo and nimh its the energy potential and internal resistance that give them the enormous power!you wouldn't need to replace speedos, most are rated to 9.6v anyway.

combining these batteries with brushless would make 15-20 min finals possible. this would take the wind out of many nitro boys arguments. sure you still need to recharge but come on - 20mins!!!! :D

the cost savings with the brushless will make mod motors obselete very soon. if they are legal at next years carpet wars here in the uk im buying one

nomaak 04-10-2006 03:30 PM

i've been watchin the li-po market for about 16 months. i've heard the horror stories and i've watched the movies...BIG DEAL!!!! what sold me was seeing the average "newbie".......say the local 13 or 14 year-old, have his dad buy all of this "dangerous" stuff, go out and run his 1st race and finish his entire day without as much as a puffy pack!
(bump it!) i'm just gonna go out and say it!!!! Li-po's have been the best thing in RC automotive since the 2000 cell...period! i got one and am never looking back! you folks who let ROAR and the rest of 'em hold you by the balls...go ahead! the technology train is passing you by and quick!! yes...i admit, there is a safety issue with them...but so is a 2nd grader if you don't treat them right!
(harsh, but i had to get it out) :blush:

nomaak 04-10-2006 03:37 PM

i also like the fact that you don't have to go all over the net to find the best matched, highest volt, super mah packs. any li-po off the shelf will do. i'll gladly pay $150 for ONE battery pack that's in 90% of it's power (after 2 years) rather than spend $420 for 6 packs that'll be only 60% in less than 9 months!

TAMIYAMANUK 04-10-2006 03:41 PM

also just look at the costs as well

linger 04-10-2006 04:25 PM


Originally Posted by Grizzbob
As has become obvious, you'll get different responses from different people, but I know for me, 2(& a half) things are what keep me from jumping into LiPo's. 1. Rules, I don't see a reason to spend that much money on new packs when no big races(like Cleveland, the Snowbirds, the Novak USTC or Vegas IIC, for example) will allow them, & 2. Cost. No matter how you slice it, $150 is a LOT of cash for one battery pack(I can easily buy 2 top notch packs from my preferred matchers for less than that) & also(this is the half part) I'd have to buy a new charger that can accomodate LiPo's(& there aren't as many of them as I'd like to see, & none are exactly cheap, & no, Rick, I'm not forgetting Orion's Advantage, nothing against it but my loyalties simply lie elsewhere). All that being said, I do suspect that eventually, they WILL become the norm everywhere, but there's no reason to rush it. I still remember when NiMh's were first talked about(& it was around 1989, believe it or not) but it took another 10 years or so to put out a useable cell, & a couple more before a GOOD raceable cell arrived(& by then it was just beginning to gain acceptance by everyone), so just be patient, it'll happen.... :cool:

Grizzbob - your posts actually make sense. I agree, $140 is a hard pill to swallow for most people.

I disagree with the charger statement though. There are $70 LiPo chargers that work awesome with 4 lines of data. More economical than NiMh chargers.
http://www.hobbypeople.net/gallery/158374.asp

So how about it Rick Hohwart - lower the price of Li-Po to gain market acceptance.

And what about ROAR? - now is the time to legalize and regulate LiPo batteries. Why race with inferior and finicky equipment? That's no fun.

Potato 04-10-2006 04:33 PM

linger,

Mind if I ask what kind of Lipo setups were used for the enduro?

Thanks!

Decathalon 04-10-2006 05:04 PM

I don't see any problem with LiPo's and Brushless Motor use, in fact we should be adopting it quicker than we or the industry is. You hear stories about houses burning down, models on fire etc. My own experience and most people I know with LiPo's in RC planes have had no probs at all. The only people I have ever heard of that had problems, were those that didn't follow the simple rules about charging LiPo's ie: 1C max charge rate. Or people that buy cheap low discharge rated packs and then try to pull 20C out of them. If you follow the rules, no probs. :nod:

As for Brushless motors, I love em. The idea of little maintenance other than the odd bearing, more efficiency and run time and more flexability in use ie: can accept wider voltage range are all big pluses. I have a Mamba system and a Sphere/ Neo system is on the way. :)

As far as standards, I guess ROAR , IFMAR or any of the other bodies need to come up with a standard size and stick to it ( example say 4800mah packs with a basic set dimensions ) then chassis makers will build cars to fit this. It's not a big deal anyway as Lipo's are lighter for similar capacity so you'd probably have run weights to get the car in the rules anyway. Easy enough to balance it then. :tire:

Lastly cost...... with Orion seemingly the only ones on the market with car specific packs, I guess lack of competition is a big factor. Yes their packs are a bit of a rip off when you consider good quality aircraft packs ( yes I know they don't have as sturdy a casing etc, but how hard or expensive is that on a mass produced scale? ) are cheap as chips now compared to Orions pack and what aircraft packs were for the same capacity only a year or so ago. I remember when aircraft RC packs first came out all the same argurments arose, but within a few years they were accepted to the point that most, I'd say about 70% of electric flyers I know use them exclusively. What do we need to do to get this change in the car RC car world? As someone pointed out before, most of the LiPo and Brushless knockers are people who have never actually used them and just go on hearsay or rumors. :weird: I thought why change when they are so expensive at first, but they got cheaper in planes and once used theres no going back, trust me :nod:

Anyway just my 2 cents worth from Australia ;)


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