Oh and have you ever witnessed a lead acid battery in a fire? That will make a big boom!
Rules thoughts
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As I stated above, weight was what finally forced me to switch to LiPo's. We're talking just shy of 5-1/2ozs, that's a hella-va lot in little 24" boat.
Sure I can adjust the outdrive (very easy) to get the nose outta the water with heavy batts, but why?? FYI: the batt is in the front of the Blast boat.
Lite weight LiPo's + lower KV motor = less wear & tear on the driveline and longer runtimes; that's a no-brainer. Probably going to make this my rescue boat, so having less weight up front will be even more important because of the home made PVC pipe jig that will be attached to the front of the hull.
Well isn't that the point of moving forward with technology? The way I see it (from this thread) is use of either "fuel" would be race allowed, wery similar voltages. And the rules state 17% give or take for voltage? (I forget, correct me if need be) but the choice is available. Now the technology advancement part, weight, lipo tec has cut the weight in half. Now to me that is a major issue in an extra pound or two when it comes to racing. Maybe more, how much difference would it be for say a 10s set up? Steve, it really is only a matter of time before our lipos become more hostile environment friendly. Military has lipos that can have a nail driven through them and they will still work, without heating up or blowing up. Chargers are riddled with safety features, at least the good ones. And the original common sense rules of charging any recharable battery still apply-use the right equipment, use the correct settings, use in the appropriate place, store and charge in appropriate locations, don't let your kids eat them or dog, its all the same stuff,,,, has anyone had a lipo battery just spontaneously burst into flames?? Not on a charger, not damaged, in a stored state, in the appropriate safe location and then cause a fire?? No.Comment
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OK on safety of Lipos and MiMh Ive been racing cars and boats competitively for 25 years, have owned/ built THOUSANDS of packs.....remember NiCd SCE's???? would buy them by the case and match them on my own turbomatchers. I have Thousands of Lipo packs and I am self proclaimed "not the most careful with them". I have had 2 lipo fires in a boat and those were on the same day in the same boat with INFERIOR Max Amps packs (it was the packs fault) I usually charge between 10-20 packs at a time on multiple chargers at high amps (10+amps on each pack) I have NEVER had a problem charging and I probably have charged more packs than most people. Using safe charge methods and good balance chargers and balance EVERY time you will not have a problem. Lipos catch on fire and burn for a long time. NiMh's EXPLODE if not treted properly, Ive had at least a dozen NiMh cells explode over the years, either in the car on the matcher and on the charger. In fact I was working on my car leaning over it and I dropped a screw If I hadnt dropped that screw and bent over to pick it up the cell that exploded in my car and got lodged in the ceiling 20 feet above me would have been lodged in my chest. The bottom line is even if you are careful with any chemisty you can still have a problem. I would rather have the lipo go up in flames than a NiMh exploding in my face. Just my opinion.
Next anyone using 8000mah in any sprint race is doing something wrong, we use 8-9000 in offshore (4 minute races) in most of my boats I use 1p setups between 5-6000 mah, My P-mono is the exception beacuse I need the weight in the boat. My most extreme setup is my N2 hydro which does use over 6000 in a heat race. Even My Big 10 cell riggers and my scale boats use less than 3000 in a heat race.
And last but not least bring any cell count you want I'll run 2 cell lipo u can run 8-10 NiMh Ill run 4 cell lipo you run 18-24 NiMh? Not afraid of any of that and most seasoned racers wouldn't be either, all of our boats are much slower in race trim than we can "actually" make them go. I would be fine letting NiMh run with us and increasing your cell count wouldn't phase us one bit. If it would keep you racing and add more people to the races than I'm all for it!!!!!!We call ourselves the "Q"Comment
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Don't think I would have had anything better to say. Agreed. Good point to make about race trim also, how many of our boats are really going to their full potential in race water? Part of the racing is getting through the ugly water and into some good water.
(Madmikepags, where about in ny are you, what places you run?-Comment
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until that post I have forgotten about a Nimh cell burst in my SV27 a few years ago...
I had no idea they could do that until it happened.NAMBA20...Caterpillar UL-1, P-Spec OM29, P-Mono DF33, P-Spec JAE, Aussie 33" Hydro-LSH, Sprintcat CC2028 on 8s, PT SS45 Q Hydro, PS295 UL-1 power, OSE Brothers Outlaw QMono 4-sale, Rio 51z CC2028 on 8sComment
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Couple questions..
Since the safety issue(s) seem to be a recurring theme... Are those so called "LiPo Safety" bags really needed? I can't see how much good they would do if the pack explodes, they're not exactly bomb proof.
Seems to me that if someone is that concerned (anal) about a pack exploding, they would get one of those fire proof lock boxes from Sentry Safe (I have a couple for my important papers) and put the pack in there while charging.
Charging... long before I had LiPo's for my boats, I purchased a couple Onyx 230 chargers, built in fan keeps it running cooler & 10 batt memory were my main reasons; ability to charge LiPo's for my heli's was another. Ok so now that I have LiPo's for my boats, I got a pair of these... http://www.electrifly.com/miscproducts/gpmm3210.html - I plug the balance tap into them (and leave it plugged in during the entire charge process) and the discharge lead into the charger.
So far no probs; is that a safe way to charge or have I just been lucky so far?? I have been charging at 1.5-amps regardless of the "C" rating, safety timer off, and actual mAh rating. If I charged my packs at 1C, I would be doing 5amps & 5.7amps - most of my packs are 5000mAh - 2S & 3S, also have two 5700's.
Any thoughts??
OK on safety of Lipos and MiMh Ive been racing cars and boats competitively for 25 years, have owned/ built THOUSANDS of packs.....remember NiCd SCE's???? would buy them by the case and match them on my own turbomatchers. I have Thousands of Lipo packs and I am self proclaimed "not the most careful with them". I have had 2 lipo fires in a boat and those were on the same day in the same boat with INFERIOR Max Amps packs (it was the packs fault) I usually charge between 10-20 packs at a time on multiple chargers at high amps (10+amps on each pack) I have NEVER had a problem charging and I probably have charged more packs than most people. Using safe charge methods and good balance chargers and balance EVERY time you will not have a problem. Lipos catch on fire and burn for a long time. NiMh's EXPLODE if not treted properly, Ive had at least a dozen NiMh cells explode over the years, either in the car on the matcher and on the charger. In fact I was working on my car leaning over it and I dropped a screw If I hadnt dropped that screw and bent over to pick it up the cell that exploded in my car and got lodged in the ceiling 20 feet above me would have been lodged in my chest. The bottom line is even if you are careful with any chemisty you can still have a problem. I would rather have the lipo go up in flames than a NiMh exploding in my face. Just my opinion.
Next anyone using 8000mah in any sprint race is doing something wrong, we use 8-9000 in offshore (4 minute races) in most of my boats I use 1p setups between 5-6000 mah, My P-mono is the exception beacuse I need the weight in the boat. My most extreme setup is my N2 hydro which does use over 6000 in a heat race. Even My Big 10 cell riggers and my scale boats use less than 3000 in a heat race.
And last but not least bring any cell count you want I'll run 2 cell lipo u can run 8-10 NiMh Ill run 4 cell lipo you run 18-24 NiMh? Not afraid of any of that and most seasoned racers wouldn't be either, all of our boats are much slower in race trim than we can "actually" make them go. I would be fine letting NiMh run with us and increasing your cell count wouldn't phase us one bit. If it would keep you racing and add more people to the races than I'm all for it!!!!!!Comment
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Now that I think about it. The rules make all the chemistries legal. They don't make them all equal. The cheapest and safest batteries I think would be made from potatoes.
We didn't accommodate lead acid either. They're great sources of power too. How many decades have we had them in our cars? Doesn't make them good RC batteries.Noisy personComment
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1.5 amps!!! it would take 3 hours to charge a 5000mah pack. I don't know about your chargers but My FMA cellpro 10xp and powerlab 6sand 8s can only balance charge, if any one cell goes too far out of balance they go into safe charge mode and only charge the cells that are lower at a .5amp charge rate. LIPOS DONT XPLODE they swell and burst into flames, it is not a violent explositionLipo sacks work because the smother the flames. You can safely charge at 1c almost any lipo pack, and the ones that say 5c charge rate easily can handle 2c, anything over that you will reduce cycle life if you do it on a regular basis. I have charged 5 cell 5s packs at 25 amps with no ill effects but only if necessary at that rate. (ie: 5 minutes to a race and your batts are only 1/2 charged!!!!)We call ourselves the "Q"Comment
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Hey Terry the chemistry isn't what he questioning its the "nominal" voltage, at the current nominal voltage NiMh cant hold the voltage under load and thus are not compettitive, if you increase by 1.2 volts you can now use 7NiMh cells.We call ourselves the "Q"Comment
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...1.5 amps!!! it would take 3 hours to charge a 5000mah pack...
Just shy of 4-hrs if want to get technical, I was just trying to do the better safe than sorry thing
The Onyx 230's don't have built in balancing, Duratrax replaced that model with the 235. Basically the same charger they just added balancing to it. Don't think the 235's have the advanced features that I've heard alot of members talk about with their chargers. Both models use the cc/cv method for charge termination.
The CellMatch's keep the cells within .01v of each other during the entire charge cycle. I did the expectant dad thing the first several times I charged LiPo's because of all the gloom & doom stuff (like Hill talks about) I had read in various threads on both this & other forums. I still treat LiPo's with the upmost of respect, I'm just not as anal as I was in the beginning.
...You can safely charge at 1c almost any lipo pack...
Several other people have told me the same thing, I will be bumping up the charge current next around. Your right, 4-hrs is an awefully long time
I don't race, so lake side charging is not an issue with me. I buy enough packs that I can spend a couple hours at the local lake. My Trax Blast & IM31 are the only one's that both use 2S, my SW26v3 will be using 3S's once I get it switched over to BL.
At present time my Rio is running 8.4v humps, not for fear of LiPo's, just the setup that's in it right now. Future plans call for changing the setup so it can run 3S's, again it's the weight thing. The humps weigh over a pound, 3S's around 11ozs.
Think I'll be investing in a couple LiPo sacks with my next battery order.
Happy boating everybody
1.5 amps!!! it would take 3 hours to charge a 5000mah pack. I don't know about your chargers but My FMA cellpro 10xp and powerlab 6sand 8s can only balance charge, if any one cell goes too far out of balance they go into safe charge mode and only charge the cells that are lower at a .5amp charge rate. LIPOS DONT XPLODE they swell and burst into flames, it is not a violent explositionLipo sacks work because the smother the flames. You can safely charge at 1c almost any lipo pack, and the ones that say 5c charge rate easily can handle 2c, anything over that you will reduce cycle life if you do it on a regular basis. I have charged 5 cell 5s packs at 25 amps with no ill effects but only if necessary at that rate. (ie: 5 minutes to a race and your batts are only 1/2 charged!!!!)Comment
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LIPOS DONT XPLODE they swell and burst into flames, it is not a violent explositionLipo sacks work because the smother the flames
I am going to do this again sometime and shoot video. These lipo sacks IMO are giving people a very risky and false sense of security. Proceed with caution.
DougComment
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Doug,
How the heck did you detonate the batts??
...These lipo sacks IMO are giving people a very risky and false sense of security... That's precisely why I asked about them
Proceed with caution... I always do, that is one of the reasons I backed down on the charge current. I'd rather wait a little while longer than deal with the alternative.
How bout putting the batt in one of these while it's charging... http://www.sentrysafe.com/Products/1/1100_Fire_Chest - Yes I realize the idea is to protect the contents in case of a house fire; but it seems to me that if they can do that, then they should be able to keep the contents contained as well. Just a thought...
Sorry Mike - I am going to have to disagree with you on this one. A few years back I detonated a bunch of 4s packs in my back yard. Most of these shot flames into the air about 10 feet and were under intense pressure for approximetly 60 seconds. Not an explosion but rather a very large torch or flame thrower type thing. Nothing at all something a lipo sack would have worked for.
I am going to do this again sometime and shoot video. These lipo sacks IMO are giving people a very risky and false sense of security. Proceed with caution.
DougComment
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Lipo fire is intense and the temp is extremely high. The sacks are not a fool proof way of averting a disaster. I have seen the video and flames shoot out from the side. I agree that it leads to misconception about its effectiveness. What bothers me is that there must be different grades of these sacks but there are no industial regulations and we can buy from a very low prize point to moderately high prize point, so does the reflection of prize serve as an indication of quality??? I have a few and the interior varies greatly from one to another, on one of them the interior feels just like plain rubber, where as the other one you can see the woven fibre glass lining.
Any thoughts?
I am careful and always maintain visual contact with my chargers when my lipo batteries are being charged, and I put them in my fire place while doing that.
To the OP: I am sorry to drift away from your original topic. I couldn't help but to ask for ideas about these lipo sacks, my apologies!Too many boats, not enough time...Comment
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