My Trampa caught fire last weekend

@Eboosted Sorry for that mate, you are lucky that it did happen in the street. I wold check those red cables once. Because when you solder them they lose lots of it’s flexibility. Because of bending one of them cold have losen up, and shorted out somewhere. Just an idea. Other cause could also be is that there was as a bad cell.

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Sorry about your board, great loss but at least it was material loss only.

Let this be a reminder for all that these toys of ours are not toys at all and take your board, open it up and double check everything. Wiring, connections, insulation, voltages, make sure it is all seated/glued/silicon-ed together, throw/re-purpose your old/puffed LiPo packs (forget about that one last ride) and so on. If you don’t open up your board frequently, you might be surprised what riding conditions and vibrations can do to the insides.

Ride on but stay safe, my friends!

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I’ve started on a new build but so far none of the parts are as high quality as what I had before :cry:.

I’m truly sorry for the lost, I couldn’t see mine burning either. But here’s the thing, I really don’t think it’s caused by balance wire as the wire is too thin and it will vaporize (act like fuse) when short due to the high current, hence it will disappear. The only only only possible reason this happens is because one of your solder join come loose (those thick wires) and slapped through the opposite side of the terminal. The other minor possible way is a loose or rubbed off shrink tube due to the vibrations overtime.

This is the thing for all builders. Adding a layer of security into the build is never an issue, this is the so damn reason why I have incorporate as much electrical protection needed.

NUMBER 2 THIS IS VERY IMPORTANT. I really do like the flexing of the board and the seamless electronics tucked under the board nicely bolted down to the deck. But again this design doesn’t incorporate safety as brick, stone, vibrations and water are underneath the board. On top of that those nice locking mechanism avoid fast fire battery disposal. There is nothing you can really do about it, while if you have a clip on case you can easily knock off burning batteries.

It huts to see the beauty going up in flames. If you need a new one, get back to us via mail.

Frank

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Flex kills packs. ITs hard to build a flexible pack.

I’ve been building bamboo mod packs for a while now and they have to flex. On flexy packs like those and this one, you have to be REALLY CAREFUL how you run your balance leads. All nickel needs to be taped over to eliminate any kind of cutting edge. All pgroups need enough slack in the connecting wires to bend. Be careful not to harden the shorter connecting wires by using too much flux and soaking up too much solder. They’ll break.

I’ve had two packs come back for repairs and i’ve learned all of this from them. When run correctly, balance leads will “fuse out” but if they have the ability to directly contact nickel or a cell canister at any point along thier path out of thier pack, while “fusing” they can easily weld to the cell or nickel and cause a more permanant short, possibly just enough to thermal runaway.

This build looked solid. Damn that’s a shame.

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First I am very sorry about your fire @Eboosted. I am also glad the problem happened during outside use and not during charging!

While I am relatively new to esk8’s I have some experience building and designing commercial lithium-ion packs for vehicles.

Here are some design rules you should TRY to follow. I will list them in what I feel is the order of importance for a typical 6-12s skateboard style pack. While a few of these are “easy” several of the design rules are very difficult to accomplish even at large companies.

1: Monitor and control cell voltage at all times

2: Monitor and control continuous current AND peak currents

3: Monitor and control cell temperatures

4: Propagation/run-away control.

While this list looks simple it is very difficult to accomplish these simple goals.

Voltage: For the automotive business, we typically use a BMS with 2 relays for redundancy to disconnect the battery from the load or charger. Beware relay/contacts can and do fail and we must expect that.

Current: Again the BMS is designed to communicate with chargers and loads to reduce current demands/supply when we approach current limits, as a backup fuses are also in place for short circuit events. Makes sure the fuses match the operating voltage or they do nothing. It is slowly becoming standard in the industry to individually fuse EACH cell.

Temperature: While ideal, it is often not feasible to measure the temperature of each cell. With a bit of testing, there is typically a small spread of temperatures of the cells and you can measure the temperature of the hottest cells in the pack. Over temperature is very dangerous because it causes damage to the separator inside the cells. This leads to “weak short” or small short circuit inside the cell, this increases the cell temp more and does more damage.

Run-away control: shit happens = vibration, things penetrating packs, boards roll into canals, bad temperature sensors, user error, and even bad cells from legit Japanese/Korean cell manufacturers so you have to make sure 1 bad cell/cell fire does not spread to the rest of the pack. This is very hard to accomplish while not causing cells to overheat.

z

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A LOT of builds I’ve seen use hot glue (flammable) between cells. I think it’s use should be eliminated all together.

E6000 is a really good adhesive Doesent stink nearly as much as silicone.

I think it’s about time the cells had internal fuses on the positive lead from the manufacturer

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I am very sorry about your Board, In first time, you can be happy that´s you have nothing broken or you fell. When you will build your next Board, then you became from me two Antispark with Fuse for free.

PM me your Adress and i sending you two for free,

Regards

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Wow this is so generous, thanks @esk8 a lot!

Guys, even though I had a hard time loosing my eboard I’m so happy to get so much support from all of you with kind messages and PMs. Fortunately I have other eboards, none as awesome as the “crispy” one, but I’m already back shredding.

I thought about a gofundme page but I didn’t feel comfortable setting that up, there are other brothers with less resources trying to build their first eboard that need more help than I do, I’m not a rich guy, but with some effort I’ll be able to resurrect the Phoenix from the ashes

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It happens to the most experienced of us… I’m still laughing!

Frank

Are you talking about these printed PCB’s?

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There’s more pics here:

Little bit more detail here. Did two builds like this

I love those PCB’s, the guides for the balance leads are slick too. How does the sense wire know which one it is in the pack?

Can’t you sell us some of those PCB’s? I know others have asked so here goes again :slight_smile:

EDIT: I mean I guess one could send the image of the PCB to http://www.pcbway.com and have them make it. But if you are selling them, I sir would be most interested in a few for a pack I am doing right now.

I also remember this, at the time I though damn these things are dangerous, I’m going to open up my enclosure and see if everything is perfect, so I did it, it was months ago, however it did happen to me later on.

I’m going to fix the batteries on my new build pretty tight

base on that, original implementation by @Blasto

Well it seems the right way to go… with all these wires sticking out the isolation of the wires looks really clean with those PCB’s.

But we really have no clue why EBoosted board exploded… but it just scares the hell out of me now!! I also have recently destroyed a Graphene 4s 6000mAh battery just started getting hot and seep liquid into its cavity. I am now being much much more cautious. Padding the crap out the batteries.

On my 12s4p pack - I am going the way @trampa Frank has. With tufnol sheath (1.5mm & 3mm) on both impact sides and a polypropylene shell and balance wires tucked away.

I haven’t series soldered the packs yet ( I was going to tonight)… so if you have some of those PCB’s for sale…please let me know !

  1. All my packs were balanced with a difference of 0.01 - 0.02V
  2. There was an additional layer of protection on the head of every cell.
  3. I applied 6 spot welds on every cell, job was mint
  4. No BMS was being used at the time of the fire

The theory of the balance wire shorting and causing fire is loosing weight as it happened to several people and that’s not enough to start fire

There must have been a bigger short, I’m leaning to be on the charging port, the port was a high quality Switch Craft, it could have been hitted by the last battery pack casing a short.

That’s the most probable thing so far.

In order to avoid this in the future, I’ll secure all individual packs from moving with some kind of stops and use more neoprene so each battery stays put and fits snuggly.