so much for "not equivalent" voltages between nimh/lipo
12-06-2006, 12:29 AM
#76
Like all things that are based on new concepts it will take some time for acceptance on a broader range or scope. It can and will make things more affordable for entry level and higher. When it is finally accepted it will then be the norm until something newer and better comes along.
This is the way of technology and the basis of our spending !
I am all for LIPOS technology and what they have to offer and like any other cell must be treated with care as with any other cell. Remember that all of the exploding incidents and fires in the past 2 years have been from NIMH. Eventually they will become the norm especially with it being cost effective for the racers. All of the governing bodies must realize racers interest come first and foremost after safety that is. But as stated the safety of all cells must be taken into consideration, if you mistreat any cell it has a potential of being a hazard.
So even to all of the nay Sayers just remember where we would be if not for the advancement of technology. Maybe running a 900 MAH pack and an MSC ! Technology will always prevail..........
This is the way of technology and the basis of our spending !
I am all for LIPOS technology and what they have to offer and like any other cell must be treated with care as with any other cell. Remember that all of the exploding incidents and fires in the past 2 years have been from NIMH. Eventually they will become the norm especially with it being cost effective for the racers. All of the governing bodies must realize racers interest come first and foremost after safety that is. But as stated the safety of all cells must be taken into consideration, if you mistreat any cell it has a potential of being a hazard.
So even to all of the nay Sayers just remember where we would be if not for the advancement of technology. Maybe running a 900 MAH pack and an MSC ! Technology will always prevail..........
12-06-2006, 08:04 AM
#77
Krunch That was an awesome post. Now thats getting to the bottom of things. My hats off!
Syndrome I think its the motor getting hotter as the run goes on. My 4800 has 7.75 max capacity after a 5 min run. I think the gearing is the killer.
If we gear perfct to the motor, the end of the run would be more consistant.
In most cases we under motor the track, and in an attemp to go faster we over gear. Any magnet no matter what is going to loose efficancy once its reached it's temp threshhold.
And Mr. Black I will add that It's Fellows like your self that help us make educated decisions for ourself. Consider your hand shaked. Later.
.....................X................
Syndrome I think its the motor getting hotter as the run goes on. My 4800 has 7.75 max capacity after a 5 min run. I think the gearing is the killer.
If we gear perfct to the motor, the end of the run would be more consistant.
In most cases we under motor the track, and in an attemp to go faster we over gear. Any magnet no matter what is going to loose efficancy once its reached it's temp threshhold.
And Mr. Black I will add that It's Fellows like your self that help us make educated decisions for ourself. Consider your hand shaked. Later.
.....................X................
12-06-2006, 08:57 AM
#79
Originally Posted by syndr0me
Mr. Black, looking at voltage discharge curves for LiPo, it does seem as though the voltage of the batteries will decrease during a 5 minute race. Would you say this is noticeable on the track?
Originally Posted by syndr0me
I feel like my car is a bit faster (top speed) in the beginning, and starts to feel a tiny bit soft by the end, very much like a NiMH pack, though less drastic. What doesn't change, however, is that the punch is always there, even if the top speed seems to fade a bit. I suppose this could be due somewhat to the brushless motor, but does the lower IR of LiPo lend to this as well?
At the KO this year several racers noticed with Li-Po they could feel when the motor went soft while as before they could not tell as there batteries got soft and much stronger rate masking the loss in motors performance. I know when we did some early testing with large capacity Li-Po's we were able to run motors for much longer then previously possible teaching us a lot about how motor loose power do to more then just bursts of heat but constant running over long periods. We even thought to ourselves that we may be opening a pandoras box to motor abuse.
Originally Posted by syndr0me
Also, if we took the 4800 pack and 3200 pack and measured their voltage during a 5 minute race, they should be about the same, right? The increased capacity doesn't affect the voltage curve during discharge with LiPo, does it?
We even had one driver swear the 3200 were faster until he realised that the weight saving s on the 3200 over the 4800 was the same wieght of a half a can of soda. Weight plays a big factor in many things and if we can make cars lighter everyone will benefit in performance and lifespan of equipment
Originally Posted by syndr0me
Hearing about new stuff makes me jealous. The opportunity to test new products before they hit the market sounds like one of the biggest perks of being a team driver, or company employee. :-)
Originally Posted by syndr0me
Also, it looks like laptops are starting to use LiPo. My fancy new MacBook Pro is LiPo rather than LiIon. If it's good enough for the world's most popular brand, it's good enough for me!
12-06-2006, 11:19 AM
#80
Hmm, I wonder if I'm experiencing a little heat fade. The motor never gets above 130 by the end of the race, but maybe that's enough to affect it, even with sintered magnets. I guess I could put a heatsink on it.
Thanks for the candid answers. We ARE adding weight to our cars to make them reach 51oz. This makes it "fair" for the guys still using NiMH, of which there are a few.
Thanks for the candid answers. We ARE adding weight to our cars to make them reach 51oz. This makes it "fair" for the guys still using NiMH, of which there are a few.
07-18-2007, 04:11 AM
#83
For club racing we need to lighten up a little. Allow Lipo and brushless in to the lower classes. I personally run Lipo and a C027 stock motor and its great. I can actually keep up with the IB4200 guys now and i didn't need to replace my charger, buy a discharger and buy an equalizer.
Club racing is about getting the numbers and having fun. For me Lipo saved my hobby because i was about ready to give up on 1:10th touring cars until i purchased a Lipo.. now i own 3 and they are great. I can charge em days before.. i don't have to cart a heap of electronics to the track and the run times are great. I do however treat them with great respect and have done small mods to my chassis to protect them with this respect in mind.
Clubs are dwindling and EP 1:10 is really suffering. I'm not so naive as to say Lipo is the Saviour but it defiantly saved me from putting my setup and ebay.
I'm for rules but lets keep the tight rules at the high end level of competitive racing where they should be.
Club racing is about getting the numbers and having fun. For me Lipo saved my hobby because i was about ready to give up on 1:10th touring cars until i purchased a Lipo.. now i own 3 and they are great. I can charge em days before.. i don't have to cart a heap of electronics to the track and the run times are great. I do however treat them with great respect and have done small mods to my chassis to protect them with this respect in mind.
Clubs are dwindling and EP 1:10 is really suffering. I'm not so naive as to say Lipo is the Saviour but it defiantly saved me from putting my setup and ebay.
I'm for rules but lets keep the tight rules at the high end level of competitive racing where they should be.
07-18-2007, 06:52 AM
#84
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and the main reason why i'm running a pro 4 with 4.5 and lipo over my r40?....
overall nitro,foam tire,time is money maintenance, expense....
B/L and lipo make RC racing fun again...
07-18-2007, 07:34 AM
#85
As someone who just spent over $200 on new lipos I feel misled. A 1 year old NiMh battery performs just as well as a brand new lipo? No wonder my lap times havnt improved.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
07-18-2007, 07:39 AM
#86
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As someone who just spent over $200 on new lipos I feel misled. A 1 year old NiMh battery performs just as well as a brand new lipo? No wonder my lap times havnt improved.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
see post # 83...and rember,the thrill of LIPO wil be there LONG after those nimh are in the Recycling box....
07-18-2007, 08:42 AM
#87
As someone who just spent over $200 on new lipos I feel misled. A 1 year old NiMh battery performs just as well as a brand new lipo? No wonder my lap times havnt improved.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
But maybe there is more to it: What does internal resistance have to do with performance? I've read that lipos have a much lower IR than NiMh.
You were probably most misled by NiMh guys who blow all kinds of smoke about how powerful LiPos are, how they have so much voltage and how they're so unfair. People who run them know they're not "all-powerful wonder batteries", we run them because they're simple to use and they last for damn ever. They're WAY close enough to NiMh to get the job done in club racing and they stay that way forever (in R/C years).
07-18-2007, 08:58 AM
#88
We are starting to mix them this year. A few guys are giving me a hard time about it. One guy in particular has his own matcher and zapper. You know he has some good batteries. I think a lot of people are just scared to loose their advantage. They say it costs a lot to switch. I tell them this investment will last me a few years until the next big thing hits. Meanwhile they'll have to buy 1000 sub-c cells.
Last edited by sportpak; 07-18-2007 at 09:10 AM.
07-18-2007, 09:14 AM
#89
Good points, but a 1 year old NiMh still performs as good as a brand new lipo? That IS a lifetime in RC!
I was looking to get an edge back with some new packs and went lipo. Now I find out they are really not any better than my old and flat 12 month old NiMhs.
Saving time and money doesnt mean much when the guys I race with have a performance advantage because they stayed with NiMh and I didnt. No where in the results does it say that I was able to charge my pack up in 10 minutes instead of 30 does it?
I guess I can still use them to practice.
I was looking to get an edge back with some new packs and went lipo. Now I find out they are really not any better than my old and flat 12 month old NiMhs.
Saving time and money doesnt mean much when the guys I race with have a performance advantage because they stayed with NiMh and I didnt. No where in the results does it say that I was able to charge my pack up in 10 minutes instead of 30 does it?
I guess I can still use them to practice.
07-18-2007, 09:25 AM
#90
Good points, but a 1 year old NiMh still performs as good as a brand new lipo? That IS a lifetime in RC!
I was looking to get an edge back with some new packs and went lipo. Now I find out they are really not any better than my old and flat 12 month old NiMhs.
Saving time and money doesnt mean much when the guys I race with have a performance advantage because they stayed with NiMh and I didnt. No where in the results does it say that I was able to charge my pack up in 10 minutes instead of 30 does it?
I guess I can still use them to practice.
I was looking to get an edge back with some new packs and went lipo. Now I find out they are really not any better than my old and flat 12 month old NiMhs.
Saving time and money doesnt mean much when the guys I race with have a performance advantage because they stayed with NiMh and I didnt. No where in the results does it say that I was able to charge my pack up in 10 minutes instead of 30 does it?
I guess I can still use them to practice.