I’ve never had a deck last long enough but probably don’t have a memory capable of storing such subtlety
How many lipo fires you aware of? How many ion cells? I have yet to hear on the site a firsthand account of a lipo fire but heard a couple for ion.
Ion packs are often made by numbskull nubies but even seasoned speedsters create rigid snowflake-like designs prickly to look at and bend with fat cylinders and thin belts looking like they will snap. Maybe they douse with tape n stickers and glue and shrink but give me a fat golden plug from superhobbyking. I’ve had ion hissing in my ear after having one of the many mystery tabs of that pack cutting somewhere and I run it outside and hours of dealing with it and money lost. maybe the perceived dangerous high power of the lipo blowing apart any short is it’s own best safety feature, never allowing a short to last long enough to get a cell hot enough to burst into flames
Having something like maybe 80 connections in a multilayer 18650 ion pack with something like 80 parts with half of them being sharp and rigid and the other half being explosive and wrapped with maybe .1mm of plastic…!! Say no more. And then let’s bolt it to an abusing environment that will constantly be flexing and bouncing the pack in a hot thermally sealed box. It doesn’t get any worse.
Battery:
Short answer: They’re both safe if built and used properly.
Personal answer: Lipos are more prone to fire than lions. I’ve spoken to suppliers like Jauch and Saft which are considered big players in europe and they both share this opinion. Saft even stopped providing lipos solely due to safty concerns. If you ask the inventor of the lithium chemestry (John B Goodenough) he’d tell you that putting these batteries into a vechicle is beyond stupid and expensive with little benefit.
With the conditions that esk8 provides, alot of vibration and friction, lions cure atleast my own paranoia.
The LiIon cell by it’s one more safe, the problem I see in it is how the packs are made.
With it i need to give @Hummie right.
Affected by the low quality made packs they become more dangerous than lipos.
I’ve seen videos of them launching. On YouTube set off in a steel can bouncing around. And seen injured people’s pics. I think the position of the cell in the pack and how well held down, as they generally are, makes them unlikely to launch
If they release there energy they crazy puff gases out like a huge fart it made melded rubber flying around in my home… if you get this hot shit in your face, than happy birthday…
Quick question regarding the safety of li ion packs, what is the diameter of the anode?
I think some fish papers aren’t perfectly fitting them and maybe with using nickel that is equal or smaller the risk of touching the kathode from folding packs could be reduced?
Not sure what width nickel you’re using but 10mm-15mm should be fine. The fishpapers are only meant as bumpers where friction is prone. I usually hotglue between gaps quite extensivly just to be sure.
18650’s are designed to vent the same way every time and will never be punctured and shorted by simply prying tools. There’s just so many variables with the lipo’s.
I have a bunch of Li-ion (30q 25r HB2) as well as some old lipo’s from laptops. I could probably arrange some test if you wanna see anything lol.
But I will much more confidently over discharge/charge and 18650 than a lipo any day of the week.
I think you’re on to something here. If you’re holding a single lipo in one hand and 10 loose Li-ions in the other of equal capacity, you’d probably be happier holding the li-ions.
But when you chuck 50 solder joints, flexibility, vibration abrasion and the other myriad of things that make batteries fail you might be better off with a few big fat lipo’s.
I;ve been using lipos for many years in smaller sizes and I’ve seen them puff, smoke and short quite a few times but perhaps I’m desensitized to it all, it doesn’t worry me much. If treated with respect they are just like any other tool that could chop your hand off.
I can’t speak to the batteries as I’ve only used lipos.
But I did notice over about the course of a year my homemade longboard did get more flexible. It was 5 pieces of 1/8” plywood glued and clamped together. When it was first completed I could jump on it with no flex and now a year later I can feel a little more bump absorption while I’m riding. I’ll also note I rode mostly on bad roads with hard wheels for ~5 miles a day during the school year, non-electric either just pushing so that might add to it?
Every battery I build has ‘flex’ built in to it. Safe flex that is… I’m not talking a thin nickel strip that we’re relying on to bend with the flex of the deck… I’m talking silicon coated 10awg wire and 15mm x 2mm braided copper tape… Plus, not to mention kapton tape in-between the parallel packs that are going to rub against each other, to stop it rubbing through the crazy thin heat shrink and causing a short… then the whole thing’s wrapped in kapton tape to prevent heat build up melting the heat shrink (should it occur), then of course, wrapped in a fairly thick, course but flexible heat shrink…
If 18650 li-ion packs are made correctly, they’re much safer than easy-to-pierce and easy-to-make-puff-up lipos…
regarding decks, yes; the mechanical strength of wood comes from the density of the wood fiber, and softer woods will degrade faster than hardwoods
(physical pressure, humidity, temperature, mechanical stress, pH, chemical adsorption from things, salt on the road, UV exposure from the sun (I once killed a Loaded Vanguard by leaving it outside one winter) etc.
Here my theory in liion vs lipo. In the real world, a lipo is easier to oumture and therefore easier for catastrophic failure.
But in our application lipos are protected by enclosures and have a lot more slack on balance wires. This makes shorting less likely on a lipo pack than a li-ion pack.
I think, from what I’ve seen , it’s shorts on balance wires that cause the majority of the battery pack fires in esk8.
Do decks lose their stiffness or spring over years of use [?]
Yes.
Firm decks stay stiff longer. Softer decks go flaccid faster. Use, weight and water makes this happen accelerates the separation of the ply’s…
Home made decks degrade faster generally than bought decks.
While the cellulose fibers can degrade, normally it is the glue interface that holds the board together that breaks down fastest in my experience. Part of the advantage commercial boards have is the increased vacuum/pressure which leads to increased adhesion of the ply’s. [example] WhitePony made some really nice Vanguard type decks here on the forum. They were great at first, but he reported a loss of energy return over time and went back to his loaded.
lipos [?]
I have three pairs I have been using for years (1.5) on eSk8, still waiting to throw any out.
caveat: use cycle at resting = 4.15-3.7v
it made melded rubber flying around in my home… if you get this hot shit in your face, than happy birthday…
