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View Full Version : More Lipo Questions from a new guy.


frvrngn
11-21-2005, 06:08 PM
OK, I have read, watched and listened to others on the dangers of LiPo's. Some people have never had a single issue with them, others like the fire post have serious issues with them.

What makes these RC LiPos so dangerous?? LiPos are used in so many things now and you dont see these kind of incidents. Now, granted we are on a worldwide forum so one persons bad incident gets broadcast all over quickly, but still. My cell phone uses Lithium batts and I have dropped, kicked, charged and discharged the thing thousands of times with no issue. My laptop has Lithium, and nadda. My digital camera and camcorder - nadda. MP3 player, no issues. Now you are even seeing TOYS with them installed (the Aero Hogs micro planes everybody loves has a baby LiPo). Now, its only charged by the transmitter pack, but its a Lithium battery. I would think that would be the last place you would want to mass produce and install them; a kids toy that is sure to be wrecked, stepped on, left in the rain, dog chewed, you get the point... if they are really so dangerous. I could just see the lawsuits now. Little Johnny's toy burst into an intense fireball and burned down my home. Or even, his little toy doesnt burst but instead leaks lots of deady fumes and now Johnny is in the hospital. Lastly, they are now showing up in power tools. Milwaukee just released their Lithium powered tool set. Now I know that I dont baby my cordless tools and every guy I have worked with doesnt. They get beat up like crazy. They also get abused like crazy, meaning used for things they really arent meant to be for. Again, seems like the last place you would want a "fragile and dangerous" Lithium battery to be is in a cordless tool that will be dropped onto concrete, tossed around, be used in extreme temps and weather, etc...

So whats the deal with rc packs? Cant they do something to make these things more robust and safer without having to resort to mega dollar chargers, taps, leads, testing equipment, etc. If a cordless tool pack can be dropped onto concrete and still work, why are rc packs so fragile? I have to think the cordless tools packs are padded inside their case, but again most cordless tools arent handled very gently. I also know that 99% of the people out there dont think twice about charging their lithium powered gadgets. Even if they did, they wouldnt be thinking it would turn into a giant toxic fireball if something happened.

Geoff_Gino
11-22-2005, 05:46 AM
OK, I have read, watched and listened to others on the dangers of LiPo's. Some people have never had a single issue with them, others like the fire post have serious issues with them.

What makes these RC LiPos so dangerous?? LiPos are used in so many things now and you dont see these kind of incidents. Now, granted we are on a worldwide forum so one persons bad incident gets broadcast all over quickly, but still. My cell phone uses Lithium batts and I have dropped, kicked, charged and discharged the thing thousands of times with no issue. My laptop has Lithium, and nadda. My digital camera and camcorder - nadda. MP3 player, no issues. Now you are even seeing TOYS with them installed (the Aero Hogs micro planes everybody loves has a baby LiPo). Now, its only charged by the transmitter pack, but its a Lithium battery. I would think that would be the last place you would want to mass produce and install them; a kids toy that is sure to be wrecked, stepped on, left in the rain, dog chewed, you get the point... if they are really so dangerous. I could just see the lawsuits now. Little Johnny's toy burst into an intense fireball and burned down my home. Or even, his little toy doesnt burst but instead leaks lots of deady fumes and now Johnny is in the hospital. Lastly, they are now showing up in power tools. Milwaukee just released their Lithium powered tool set. Now I know that I dont baby my cordless tools and every guy I have worked with doesnt. They get beat up like crazy. They also get abused like crazy, meaning used for things they really arent meant to be for. Again, seems like the last place you would want a "fragile and dangerous" Lithium battery to be is in a cordless tool that will be dropped onto concrete, tossed around, be used in extreme temps and weather, etc...

So whats the deal with rc packs? Cant they do something to make these things more robust and safer without having to resort to mega dollar chargers, taps, leads, testing equipment, etc. If a cordless tool pack can be dropped onto concrete and still work, why are rc packs so fragile? I have to think the cordless tools packs are padded inside their case, but again most cordless tools arent handled very gently. I also know that 99% of the people out there dont think twice about charging their lithium powered gadgets. Even if they did, they wouldnt be thinking it would turn into a giant toxic fireball if something happened.

Thing is. All of those other gadgets have taken as much of the "human" element out of the equation as the manufacturers can.

Mostly "humans" can't change the charge rate or set the cell count so the charger takes "charge" of the "human" element.

I have read all of the posts on the garage fire and really feel for the guy's loss. We should all heed the lesson to be learnt here - Do NOT abuse the LiPo's and NEVER go above 1C while charging and never get the cell count wrong.

If a LiPo on charge gets even slightly warm take it outside immediately, this of course means that the LiPo must be constantly watched while on charge.

How many of us walk away from the LiPo on charge and go and fly another airplane?

Will you let one crash while you run and try to put out the fire?

Geoff

ragbag
11-22-2005, 10:43 AM
In the thread he admits to buying a bunker box and forgetting to put the lid on it.
He went upstairs to do some work.

Break a one rule and you are taking a chance. Each added rule adds the percentage of oops!

When crossing the street always look left then right.

Unless you are in Japan.

Been there, done that, almost an oops.

Another rule broken. Glad the driver was paying attention. Like him I was in a hurry.:o

By George

Unbalanced prop
11-22-2005, 05:07 PM
OK, I have read, watched and listened to others on the dangers of LiPo's. Some people have never had a single issue with them, others like the fire post have serious issues with them.

What makes these RC LiPos so dangerous?? LiPos are used in so many things now and you dont see these kind of incidents. Now, granted we are on a worldwide forum so one persons bad incident gets broadcast all over quickly, but still. My cell phone uses Lithium batts and I have dropped, kicked, charged and discharged the thing thousands of times with no issue. My laptop has Lithium, and nadda. My digital camera and camcorder - nadda. MP3 player, no issues. Now you are even seeing TOYS with them installed (the Aero Hogs micro planes everybody loves has a baby LiPo). Now, its only charged by the transmitter pack, but its a Lithium battery. I would think that would be the last place you would want to mass produce and install them; a kids toy that is sure to be wrecked, stepped on, left in the rain, dog chewed, you get the point... if they are really so dangerous. I could just see the lawsuits now. Little Johnny's toy burst into an intense fireball and burned down my home. Or even, his little toy doesnt burst but instead leaks lots of deady fumes and now Johnny is in the hospital. Lastly, they are now showing up in power tools. Milwaukee just released their Lithium powered tool set. Now I know that I dont baby my cordless tools and every guy I have worked with doesnt. They get beat up like crazy. They also get abused like crazy, meaning used for things they really arent meant to be for. Again, seems like the last place you would want a "fragile and dangerous" Lithium battery to be is in a cordless tool that will be dropped onto concrete, tossed around, be used in extreme temps and weather, etc...

So whats the deal with rc packs? Cant they do something to make these things more robust and safer without having to resort to mega dollar chargers, taps, leads, testing equipment, etc. If a cordless tool pack can be dropped onto concrete and still work, why are rc packs so fragile? I have to think the cordless tools packs are padded inside their case, but again most cordless tools arent handled very gently. I also know that 99% of the people out there dont think twice about charging their lithium powered gadgets. Even if they did, they wouldnt be thinking it would turn into a giant toxic fireball if something happened.

First of all we are using our cells much harder then cell phones, laptops and etc. We want fast charges with high discharge rates. Over discharge and over charge is where the problems occur for lithium cells.

Cell phones only use one cell so they are much safer to charge. Laptops and other electronic devices have protection circuits built into the packs to prevent any cell going over voltage on charge and exploding. Not sure about the tool pack but they probably also have a protection circuit built into the pack to prevent over charging. These cells are also charged slowly with specialized chargers. The discharge rate is low compared to what we use in our planes.

Manufacturers of high discharge (and high charge) lithium packs are getting better with specialized chargers and balancers to make pack safety much better. A few of them are Kokam, Thunder Power and Duralite. IMHO it will keep getting safer and cheaper as more competition brings the prices down and safer products to the market. Just a couple years ago there was no safety devices any where and packs had to be watched very closely at all times. We still have to be careful and check everything three times and monitor what we do.

Doug

frvrngn
11-22-2005, 05:57 PM
The Milwaukees are 28V high discharge Lithiums with a 1 hour fast charger. To me, that is running a battery pretty hard. I have to assume there are safty guards in place, and these tools are anything but cheap - but neither are high quality RC chargers and Lithium batts.

I have to agree that they are taking the "human factor" out as much as possible with these. You have one style and size of battery with one dedicated charger. Plug "a" into "b" and let the safety devices do their thing with out worries about cell count, charge rate, etc. Still seems kind of risky to me to put a battery that has a fairly easy potential to be a toxic fireball into kids toys and other items that will get hard use.

Again, I know many people that have had zero problems with Lithiums since they have been introduced. I am sure down the road they will get much safer and easier to use. I also know we (meaning rc hobbyists) are continually trying to push the envelope and things happen. We are probably on the cutting edge of LiPo's and want the latest and greatest. I happen to be in the same boat as other hobbyists and I have read all the warnings and dangers. I also am pretty fanatical about my hobbies.

It just seems like a fairly large risk to be taking. There are many people out there who are pretty clueless and sales people who are just as clueless. Joe Consumer walks into LHS and buys a nice large LiPo and doesnt have a clue that it can very easily burn his home, car, etc down in a heartbeat if abused. He's used to plugging in his Nicad into the charger and going to bed without worries. Not even a month ago I was in one of my local LHS and a Joe Consumer walked in with a TP Prolite he just bought that was so puffed it was almost round! He was still trying to use it and wanted to know why he couldnt get any power out of it even after charging it continuously overnight! He was just casually walking around with it in his pocket too. It was all the LHS owner could do to get him to leave the store. Joe C. thought everybody was nuts (and pissed) that his brand new $$$ battery that was supposed to be so great was dead and very dangerous at this point. He wanted to just toss it in his trash or a dumpster. That could have made some pretty fireworks.

Unbalanced prop
11-22-2005, 06:15 PM
Again, I know many people that have had zero problems with Lithiums since they have been introduced.

Knock on wood,..............but I have had zero problems with lipols after many many charges and discharges and over two years of use with many different brands. I do treat them just like a gun. I always assume it is loaded and dangerous because I know that as soon as I get complacent, they will jump up and bite me in the butt!:eek: Someday the average Joe may be able to just plug and play them safely, but that day isn't here yet, but I can see a light at the end of the tunnel now.:)

Doug

frvrngn
11-22-2005, 06:26 PM
I just saw a thread on another board where they are thinking of buying the V28 Milwaukee packs and taking them apart. $150 for the pack and $60 for the charger for a 8S 100Amp Lithium pack. See - we are always looking to push that envelope;)

If it works, seems like a pretty cheap deal. Wouldnt have to worry about the pesky settings either if you leave it as is. Some poeple were talking about taking the cells apart to get a couple 3S packs and a 2S for $150. Then you're back to square one with getting things set right.

Unbalanced prop
11-22-2005, 06:45 PM
I just saw a thread on another board where they are thinking of buying the V28 Milwaukee packs and taking them apart. $150 for the pack and $60 for the charger for a 8S 100Amp Lithium pack. See - we are always looking to push that envelope;)

If it works, seems like a pretty cheap deal. Wouldnt have to worry about the pesky settings either if you leave it as is. Some poeple were talking about taking the cells apart to get a couple 3S packs and a 2S for $150. Then you're back to square one with getting things set right.

The charger is probably of no value unless you are charging 8S packs. The cells may not be great for us depending on the capacity and discharge rate. Taking the pack apart may not be the easiest and safest thing to do either, but I am sure somebody will give it a shot.:rolleyes:

Doug

hoppy
11-22-2005, 08:18 PM
They are advertised as a Lithium-ion battery.

Here's the info:
Earlier this year, Milwaukee Electric Tool Corp., a unit of Hong Kong's TechTronics Ltd., introduced slightly less powerful 28-volt cordless tools powered by lithium-ion batteries made by a Canadian unit of Taiwan's E-One Moli Energy Corp.

http://www.molienergy.com/

One of the batteries in their literature is a 2C Li-ion 2AH cell.

hoppy
11-22-2005, 08:30 PM
Here is why they are safer- http://home.hamptonroads.com/stories/story.cfm?story=94934&ran=97724

"The technology driving A123 is based on discoveries by MIT professor Yet-Ming Chiang, a materials scientist. Chiang, who co-founded A123, said “research in batteries is very seductive ” because it initially looks easy to boost power, but many variations turn out to shorten battery life or make batteries so unstable that runaway oxidation explosions occur. “They are chemically complex, electrically complex and mechanically complex,” he said. A123 representatives say it coats an aluminum electrode inside the battery with nano-scale particles, a few hundred atoms in size, of lithium metal phosphate. Company representatives decline to disclose more detail, but Chiang says the phosphate is safer than the oxide-based chemistry used in lithium-ion batteries today. He says that when compared with the same weight of larger particles, the nano-scale particles release more ions, freeing electrons to create an electric current. "

Unbalanced prop
11-24-2005, 03:57 AM
Thanks for the info Hoppy...............Wish I knew what the heck all that meant!:confused::( I do like the "SAFER" part though. Hope the technology can filter down to us.

Doug

ragbag
11-24-2005, 01:07 PM
We always dicuss the lipo batteries exploding. We don't use lead acid batteries in anything.

They will explode also, throwing acid all over the place. Many people jump off a car by connecting the jumper cables to the battery. WRONG!!!

Positive lead to the positive of the dead battery, negative lead to the frame of the car.

If the jumpers are placed on the battery it causes the dead battery to put off a gas fume that is very explosive and if an arc is caused while trying to start the car or when disconnecting the jumpers it will ignite.

The first time I was aware of this was back in the 60's. what saved the fellow doing it was it was a VW and the battery was in the back seat and when it lit off the seats protected him.

The telephone company that I retired from used banks of batteries in their equipmentr in the field,when we had battery run away it was a great explosion. Sometimes 24 12 volt deep cycle batteries in a cabinet.

WHAT'S THE POINT!!!!!!!!!!!!

If you kill the battery in your car charging airplanes, reread the proper way to jump off a car.

By George