The Proper Way to Build a Lipo Pack

[mechanix]

I just built my lipo pack and have been having second thoughts as to if I did it the correct way. How durable are these packs? Is it ok to just stack them like legos, or do they need cushioning between them?

Here is a pics of one of my packs, notice how the sides of each pack are touching each other directly:

 

[johnrobholmes]

How rough do you expect the ride to be? Will the packs be laid down perfectly flat, or at an angle?

 

[geetarboy]

Hey Mechanix, The padding in-between the individual packs is probably a good idea. I just stack mine up inside a topeak bag and pack a fluffy towel on top of them, I know they're boucin around in there, but have never had a problem...yet Mark

 

[dogman dan]

I'd be the most concerned about poking and rubbing on the outer edges of the pack, rather than them rubbing on each other. Particularly what might be on the bottom. I like the box inside a box, or box inside a bag method. So make up some kind of tight fitting container for it. Coroplast, poly from storage totes, and aluminum cookie sheet are the materials I've made my battery boxes from. I've never damaged a cell on some pretty rough rides.

 

[mechanix]

Thanks for all the replies,

Johnrob- It's going to be a pretty rough ride, it's going on a downhill-type build, a lot of off-road. The orientation of the packs is going to be the same as the picture shows.

I think I'm going to re-do this pack, I have too much invested in this pack to cut corners. Any recommendations for a good type of padding for in-between the individual packs?

Joel

 

[johnrobholmes]

Neoprene and old motorcycle tubes are my favorite packing materials.

 

[GGoodrum]

You don't need any padding between the packs at all, and it would be best to wrap them tightly, with duct tape or shrink wrap. You don't want them to have room to "puff", or expand. What I do is use double-sided tape to stick the packs together, in a manner much like the ones shown, wrap the pack in duct tape, and then shrink wrap the whole pack, twice.

-- Gary

 

[dogman dan]

If you are going to do internal protection, then you need chafe resistance more than internal padding. I have chafed the shrink wrap in spots on an otherwise unprotected nicad pack. Maybe some thin polyethylene sheet would be good, like from cheap notebooks or file envelopes. Outside the pack, my lipo is being carried in a box made of coroplast political signs. Then that box goes in a toolbox.

I did see a thread about using water bottles as shrink tube. Or you could get some shrink tube somewhere and double shrink wrap each pack. Lastly, you could just get some thick clear packing tape, and just tape up each pack for some additional thickness.

On my street race bike, I built custom fitting boxes out of wood and aluminum sheet, but the bottom has a coroplast piece for cushioning.

 

[Ypedal]

http://endless-sphere.com/forums/viewtopic.php?f=6&t=18296&start=30

I went a few steps further and layered ABS plastic between each pack, it adds bulk but it's well worth the half inch extra... Last week the Norco fell over on it's side ( my fault ) and the pack fell on the corner of the coffee table !!!! ... zero damage ! :wink:

Duct tape would have = House Fire.

 

[El_Steak]

I poked and killed one of my pack because of careless packing. Just a little poke in the foil is all you need to kill a cell.

Now all my packs are individually shrink wrapped (thick rubbery shrink wrap over the blue plastic wrap).

I have 12 x 6s packs. Once they are shrink wrapped, I tightly tape the packs in groups of 3 and put them in LiPo sacks. (not sure the LiPo sacks are all that useful but I have them).

I then split the 4 Lipo sacks in 2, putting each pair of Lipo sacks in tight fitting purposely built boxes (similar but not as nice as Ypedal's). Finally those boxes are inserted in my MEC panniers where they fit tightly with the help of a bit of foam.

So I have bag -> foam -> box -> Lipo Sack -> Thick black shrink warp -> Thin blue shrink wrap -> cell.

 

[dogman dan]

Impossible to say you ever have too much. Here's one example of a coroplast box to protect the lipos. Ya know, the political and real estate signs. View attachment Coroplast lipo boxes.jpg

A three pack in the middle, with two pack and four pack on either side. On my dirt bike, two of the three packs make a nice square that fits good in my metal box bolted to the bike.

Here we see what I have bolted to the racing bike. Corplast pads the bottom, and tightens the fit on the ends, but I have put some clear tape on the inside of the aluminum plates, hoping plastic on plastic won't rub much. This one is designed to take a crash. I plan on just using package tape to secure the cells into the box while racing. View attachment Lipo box side view.jpg

 

[Seriousknot]

I am in the process of building enclosures of fiberglass that hold 4 lipo packs. I have some left-over foam from a Pelican Case that I thought about putting in the bottom since the packs will be sitting vertical. Here is a pic of the Male mold I am working on. If I wanted to get real particular, I could order some Vinylester resin and make these flame resistant. What I would like to see is some pics of the wiring and connectors as well as cut off switches.

 

[dogman dan]

That will be sweeeeet!.