rc1973

I'm just getting back into RC and the more I read safety precautions about LiPo batteries, the more they scare me. I'm not that concerned about a slow build to a fire...I have a concrete, 15 ft. by 15 ft. slab I can charge on, in a fireproof bag. What I'm more concerned about is one of these batteries EXPLODING in my face.

Am I being overly cautious?

Do they not suddenly explode?

If I decided to stick with a 7-cell, 5,000 mah NiMH, what type of run times could I expect on a brushless Slash 4x4?

Any input is appreciated, I'm so undecided at this point. It's holding me back from making an RC purchase.

Thank you!

scott36

My Feedback: (54)

your being overly cautious....
no they don't just suddenly explode, unless reasonably caution is followed with there use ..

DieHarder

All those warnings are just to keep them companies from getting their ***** sued off. I actually keep 7 lipos in a drawer of my workbench all together in my BEDROOM! I charge them on my workbench, just keep any paper flammables away from them while they're charging. Lipos are pretty tough. They don't explode unless the actual lithium catches on fire or comes in contact with water. The lithium cells are sealed within a metal wrapping inside the battery, so if you get the battery a little wet or bring a flame near the battery, it's not going to explode. I fully submerged a Venom 2S for three minutes when I landed my truck in a pond, and it charged right up normally afterwards, no explosions/fires. There's no gases coming from them or anything like that. Just charge them at the correct amps and use 'em! You'll love the big power they give!

DieHarder

You'll have decent run times and it'll work good, but you really should go to a 2S lipo. I run a VXL system in my Evader using 2S sometimes 3S. It screams pretty good some awesome power and speed on 2S. With 3S, it pushes 65mph on asphalt speed runs. I have to mess with aerodynamics to keep it from flipping!

EXT2Rob

My Feedback: (1)

Yeah don't worry about Lipos. All the problems you heard about were mostly from ignorant people using their NiCd/NiMh chargers to charge a Lipo. As long as the pack isn't physically damaged, no worries.

zackS30

I've had 1 lipo pack puff on me, that was bcuz it was a soft pack not hard case and I used it in my exo Terra and after a bad landing the lipo came loose inside the car and the spur gear cut it open a little.
Make sure the lipo is secure in the car use hard case if the lipo is exposed like in an exo Terra.
Charge a lipo at 1a for every 1000mah so a 5000mah at 5amps. It should take about am hour.
Also NiMH batteries can't really deliver the power needed for brushless systems.

josh h

If it scares you, then order some 3s LiFe batteries from hobby king. It'll have more power that a 2s lipo and less power than a 3s. But they're safer and have longer life span than lipo's. Been meaning to order a few and try them out but I never got around to it. Here's the ones I was going to buy. http://www.hobbyking.com/hobbyking/s...ePo4_Pack.html


max amps also makes some but they're high as hell. Like 140 a piece or something.

drjav

Hey rc1973,


Welcome back to the addiction — hobby. I have a Slash 4x4 too. It’s a great truck.


I’ve been using LiPo batteries for years. A reasonable, sober adult will unlikely ever have a problem with a LiPo battery. The problems come when people don’t respect the power of the technology. Take it from my experience, a kitchen knife is more dangerous than a LiPo pack.
I will never, ever go back to NiMH batteries. LiPo batteries are so much better in every way. By the way, NiMH batteries can explode if you monkey with them enough.


For LiPo safety:
Use a LiPo specific charger.
Make sure the settings on the charger are correct.
Use a LiPo safe bag (they’re inexpensive).
Don’t use or charge a damaged pack.
Keep LiPo packs dry.
Don’t let a LiPo pack get over 120°F. At 140°F a LiPo pack will fail (fire). Thus, don’t store a LiPo pack in your sealed up car during the hot days of summer.
Use common sense.
Don’t hastily work with LiPo packs - haste makes mistakes.


That’s it.


Feel free to ask us old timers anything.


Again, welcome back to the hobby.

PS You can get great LiPo packs for $25.00 from SMC
http://www.smc-racing.net/

rc1973

Thanks for all the help, guys. I ended up getting a Slash 4x4 VXL and a 2S 25C 5000mah LiPo, with a HiTec charger. I'm charging right now...Pretty easy so far, no problems. I feel better after these posts and after talking to the guy at my LHS. Of course, he seemed a little laid back...He said he charges his LiPo's in his kitchen and stores them in a drawer in his bedroom.

DieHarder

^ LHS guy much like me. lol

drjav

Glad to hear you went LiPo. Great decision. Bedroom drawer --- It's wiser to store LiPo packs in the refrigerator. Heat kills LiPo packs. On hot days, I have my LiPos stored in a cooler. Seriously keep them cool.

Next you'll want to throw a Castle Creations Sidewinder 8th in that Sl4sh to really perk it up.

Did I say that this hobby is an addiction?

DieHarder

The bug is about to bite...

rc1973

Yeah, I feel it.

I think I might eventually want a rock crawler, too!

Kind of a related question: Is it safe to bash with just an aluminum full or half roll cage, no body shell? Or is that too much risk of puncturing the LiPo?

drjav

Hopefully all your LiPo packs are hard-case. I won't own a soft case on a bet.

rc1973

I only have one so far, but it's a hard case.

drjav

Great! Soft case packs can get a little sharp rock lodged between it and the battery compartment and eventually create a puncture. When this happens - and I've seen it - it's not happy times.

Time for you to check out SPC and SMC. I own these manufacturers' packs. SMC are the best value currently. $25.00 gets you a really high quality LiPo.
http://spcracingbatteries.com/index....&product_id=56
http://www.smc-racing.net/index.php?...product_id=246

DieHarder

I recommend good ol' Gens Ace. They do an awesome job and always give you more for what you pay. http://www.hobbypartz.com/98p-50c-50...ProductReviews I've been told all these cheap batteries come from the same factory, but tread lightly.

rc1973

Like this inner cage, would that be enough protection without a body? Or is that asking for damage to the electronics or LiPo?

http://www3.towerhobbies.com/cgi-bin...?&I=LXABUJ&P=7

drjav

Integy. I just got a little vomit in my mouth. I have no regard for Integy. Every product I've ever purchased of their's was horrible. (insert retching sounds here) I think they use 50% butter mixed in with their so-called aluminum.


Also I don't think that that a roll cage is sufficient protection for your precious and expensive electronics. Odd stuff happens during a crash. Lexan is the best protection in my experience.


On another note, throughout the years, I have owned over a dozen or so Gens Ace packs. They are excellent. If they were still the best value, I'd certainly be buying even more of them today but I they aren't the best value now. My research says SMC is the best value currently. SMC and SPC are also excellent quality batteries - equal to, or superior to, the beloved Gens Ace.

collector1231

My Feedback: (1)

*ahem* Venom LiPOs are amazing. Lol.

But the original question; you are being overcautious. LiPOs are safer than my NiMH packs. I've had a NiMH pack catch fire due to water getting past the torn up shrinkwrap and into the contacts that connect the cells, but never a LiPO. Just store theme where ever. I keep mine in the room with the hot water tank during the winter, and on my bench during the summer.

drjav

I agree that LiPo packs are safer than NiMH but to say, "Just store theme where ever." --- with respect, this is patently wrong. Here are two reasons to keep LiPo packs cool:

#1
Permanent Capacity Loss


at 40% Charge
00 °C (032 °F) 02% loss after 1 year
25 °C (077 °F) 04% loss after 1 year
40 °C (104 °F) 15% loss after 1 year
60 °C (140 °F) 25% loss after 1 year


at 100% Charge
00 °C (032 °F) 06% loss after 1 year
25 °C (077 °F) 20% loss after 1 year
40 °C (104 °F) 35% loss after 1 year
60 °C (140 °F) 40% loss after 3 months


BatteryUniversity.com


#2
Using chemical reaction, a LiPo battery will naturally increase in temperature due to use, i.e. current draw. At 140° a LiPo pack will fail (fire). A LiPo should always be below 130° but even lower is highly recommended. Some racers say 100° is best. An overly warm LiPo may be an indication that it is being overtaxed and/or damaged.

A LiPo in a sealed car during a very hot summer day = disaster.

Let's have fun, be safe, and keep our RC investments in tip-top condition.

rc1973

I live in Florida. I was planning to store them in the center of the floor in the garage, in a fireproof bag or ammo box. Will they get too hot you think? Only other alternative is to store them inside the house.

drjav

Please refer to my post #21. I have been storing my over a dozen or so LiPo packs in my kitchen, in the bottom on the refrigerator, for many years now. I use the vegetable bin because it's never used anyways.

Most racers and advanced RC drivers I know store their LiPo packs in the frige too. Not the freezer though.

I will never charge or use a damaged LiPo battery. At $25.00 a pop, there's just no need to take a risk. That said, most of my LiPo batteries have lasted well over three years --- and I use my LiPo packs almost every day --- retirement rocks!

EXT2Rob

My Feedback: (1)

+1 Retirement Rocks!

I'll have to try those SMC packs, that's a killer value.

I wouldn't trust that roll cage either. Not necessarily because it's Integy. It just won't give the truck enough protection without the body. Integy is a bit of a sketchy outfit. The ONLY way you can contact them is by email, which is very frustrating when you have an order issue. I bought a motor fan-sink, billet steering knuckles and rear hub carriers for my Hyper TT. I got the billet pieces on sale, half the regular price, so it was worth it. The billet pieces are solid, very happy with them. The fansink is fine for the $14 I paid for it, but the fan crapped out because it got too much dust in it. Replaced the fan with a Novak unit, works great! Integy does have a few good products, but you have to choose wisely.

DieHarder

In your researching, what evidence/articles do you have to show that SMC and SPC are supposedly equivalent or superior to Gens Ace? I see your point on value as there is quite a price difference, but what makes SMC and SPC possibly better?