Electric Bikes - My ammo box LIPO Pack.

Here is my Work in Progress Ammo Box 12S4P 20Ah Pack.

This picture shows the parallel connections of the 6s 5000mAh Turnigys

http://i1133.photobucket.com/albums/m596/hessejef/Parallel.jpg

The mains come in and go out thru the buss bars shown below.

http://i1133.photobucket.com/albums/m596/hessejef/BussBars.jpg

This shows the pack with the mains and the balance cables hooked to the 1420i

http://i1133.photobucket.com/albums/m596/hessejef/Charging.jpg

Finally, the pack ready for closing. Not shown is that each side of 4 bricks is taped together. There is a 1 1/2" spacer in the center at the bottom of the box to keep the packs separated. I plan on cleaning up the balance connections by replacing the wood blocks with stripboard running down each side on top of the turnigys. I haven't sourced the stripboards yet as it seems USA suppliers have 2.54mm pitch and the HK-XH's need 2.5mm pitch. The 2.54 pitch boards may work though.

http://i1133.photobucket.com/albums/m596/hessejef/Closing.jpg

Future plan involve maybe going to 14S4P by adding 4 2S 5000mAh bricks in the area that now holds my spare tube. This is a hobby and all things are a work in progress. :)

that looks awesome! i am setting up the same thing myself 12s4p (so 20ah) with 8 turnigy 6s 5000mah packs. a few questions:

1) are you monitoring temperature in there at all? i've seen some people use bbq temperature gauges

2) what size / type connectors did you use to connect everything up? looks like andersons but 30a? more detail here would be great on connections and solder/solder-less.

3) can the charger charge everything at once like that or do you need to split / reconfigure for charging? the hyperion can do 12s?

thanks! i'm very new to lipo so my questions are probably really noob...

Anything requiring an ammo box, to keep me safe, gives me pause.
I was very recently planning on going Lipo and I'm no noob..
But I read on another forum, that a guy had a catastrophic (big fire) failure of a Lipo pack and it wasn't even hooked up to anything.. (It was just sitting on a shelf).
Message to noobs.. Make sure you know EXACTLY what you're doing before you "play" with Lipo.
At this point, I'm afraid of the stuff.

I've directly shorted a LiFePo4 pack and left it shorted for over 20 minutes with no problems (except cell dying). Since I can do that to lifepo4 with no danger, I'm sticking with that!!

I read about the lipo pack going on fire as well but it seemed like a really isolated case to me (meaning that it was the first time I ever read anything like that). Logic would tell me that if these things were that unstable, the RC community wouldn't be able to use them, stores that carry and stock them would burn down, hyundai sonata wouldn't be built with them, etc. It just can't be that bad and unstable...can it?

The ammo box is definitely not a requirement but is a way to really play it safe. Safety is definitely important but those ammo boxes are also pretty heavy. If one of the reasons to go lipo is weight then the ammo box may very way tilt the edge back to lifepo4.

RVD: the bussbars are from Home Depot GBK10CS They're mounted to Dollar General Cutting boards. The wire is 12Ga silicone tinned at the bussbar end. The connectors are 45 amp andersons. The Hyperion 1420i can do 14S. I don't reconfigure anything. The balance connectors plug directly into the Hyperion and the Mains connect to the discharge wires. What I have can best be described as a single 12S 20Ah Pack. Each cell just "happens" to be divided into 4 containers.

Sangesf: Yes, one should thoughly understand and respect the power that LIPO contains. I studied the chemistry for 3 months before commiting to it. It isn't a decision to be taken lightly.

I like your use of the buss boards! Found your pics on Endless Sphere this morning too. :)

I'm waiting on my stainless steel battery boxes to be welded up, but shouldn't be too much longer before I'm running the same size pack. :) Have balanced all my LIPO's and charged them to 60% one at a time on my 1420i. Will check again before I tie them all together.

Also - for the guy that had a pack puff up and vent on him, wasn't he only bulk charging? For some reason I don't recall him keeping an eye on the individual cell voltages, or for that matter, even balance charging.

Corkscrew: anxiously awaiting to hear about your EV Grin. What's the ETA?

thanks. as for your use of the ammo box, i like the idea of the box since it's relatively fire proof. but in the off chance that a lipo does catch fire in there, you've got 8 packs and a lot of gas and pressure buildup. Are you drilling some vents to relieve all of that pressure so that it doesn't turn into a bomb?

i'm still a total noob at this and don't quite understand how to connected everything (although i do understand it in theory and your explanation) so i'll just study that a bit more. sorry for the questions (you don't have to answer these if you're annoyed).

i'm probably stating the obvious and also making dumb mistakes but it looks like you've connected each row (2 batteries) in series using 45a andersons. so you made 4 12s battery packs. then you hook them up in parallel with the buss boards (left for all the reds, right for all the blacks). you then have a red black coming out of the buss boards for your main power supply. so you have your 12s p4 setup.

the balance cables are connected with the 4 on the right and the 4 on the left so you have 2 sets of balance cables coming out to plug into the charger. did you make this balance cable (where you take 4 balance cables and make them 1) or did you buy it?



i've seen some setups where you also run red/black connector from the andersons (where you set up the batteries in series) to also be connected to each other in series. is that just unnecessary? see the diagram here: http://ebikerider.blogspot.com/2010/06/possible-remedy.html - i guess the point is in case one of your lipo packs goes back, then you may overuse the 2nd pack in that series. On a possibly similar note, did you consider the use of one of these: http://www.tppacks.com/proddetail.asp?prod=EBKE-2x6s-LVC

RVD.

No problem on the questions. I like how they make you look at things outside of the box you've formed.

Most gas build-ups should be released thru the Cord grip connector shown between the bussbars (has a blue cap to protect the wires) in the second photo.

I considered the bad brick situation you described. Look at the top photo. see the 4 red Anderson's connected to the 4 black Andersons. Current must flow thru each pair of side by side bricks. If one brick stops conducting the brick next to it has no way of discharging other than thru the tiny balance wires. Right now the tiny wires will just burn up. That's what the strip board will solve. it will contain fusable links to handle over current in a manageable manner.

I have the TPPacks kit you mention. As it's designed for a 12S connection and not a 14S I've decided to wait until after I decide if I want to add the 2 more cells. I'm pretty sure I can modify it to work on the stripboard with the purchase of some more componets. I have a Cycle Analyst for overall LVC control. Another thing I need to decide is what to do with the signal coming from the Tppacks board. When more of them get used I'll get some feedback on how to best use the data.

One thing I haven't discussed is the testing of the bricks before paralleling them together. Each pair (side by side) was discharged (used) for around 10 cycles charged and balanced seperately. I know I have 8 good bricks to start. I also figured out that sooner or later I was going to make a mistake connecting them together.

Keep the questions coming I'm sure you'll come up with something I need to consider. You'll also come up with questions that someone else wants to ask but is afraid of appearing too noobish. My feeling is Noobs will inherit the forum.

Corkscrew: anxiously awaiting to hear about your EV Grin. What's the ETA?

Who knows at this point. :)

I stripped the trike down last night - going to changing derailuers, shifters, brakes & levers, chain tubes, rear rack, and have to order a new idler because my replacement has the wrong shaft size. Might order a few MAXI fuse holders too, or more specific Anderson panel mounts, but we'll see.

EV wise, I got my TPPacks boards from my brother last night, just have to add a few trike-side +/- wires. The last thing I'm waiting for is my Cycle Anyalyst, which should be here any day now. My battery boxes are being built by some friends at their shop, so I'm hoping to take the frame down to test mount those in the next few days.

Once I have the trike back together, I'll figure out where I'm mounting the TPPacks board, my 12v converter etc. I bought 8 12" balance extensions too, as I'll have 4 batteries per box. Hoping to mount the TPpacks boards in the center somehow. Then do up my wiring harness and hope it doesn't go *boom* when I hit the throttle. :)

Debating going to 14S just because your charger can handle it all at once, or do you really want the higher voltage? :)


the balance cables are connected with the 4 on the right and the 4 on the left so you have 2 sets of balance cables coming out to plug into the charger. did you make this balance cable (where you take 4 balance cables and make them 1) or did you buy it?They look like (or are at least similar too) the adapters sold by progressive RC.

http://www.progressiverc.com/index.php/parallel-6x-balance-adapter.html

I'm scared of lipo too. There is a thread on endless-sphere which enumerates dozens and dozens and dozens of LIPO fires, through physical damage to cells, over or undercharging, or nothing at all, just that they are touchy. Be very very careful with these packs. When they go up they burn like hell.

I got them at epbuddy. http://epbuddy.com/index.php?main_page=product_info&cPath=14&products_id=59 probabaly the same cables. I will say though you're a very patient guy. Of course the weather there may be worse than here. It rains every day and is rather cool for my much skinner body.:)

I'm scared of lipo too. There is a thread on endless-sphere which enumerates dozens and dozens and dozens of LIPO fires, through physical damage to cells, over or undercharging, or nothing at all, just that they are touchy. Be very very careful with these packs. When they go up they burn like hell.

There are also dozens of threads of people using them with no issues. :) Just have to pay attention to the golden rules of LIPO.


I got them at epbuddy. http://epbuddy.com/index.php?main_pa...products_id=59 (http://epbuddy.com/index.php?main_page=product_info&cPath=14&products_id=59) probabaly the same cables. I will say though you're a very patient guy. Of course the weather there may be worse than here. It rains every day and is rather cool for my much skinner body.:)

Eh, I wouldn't say I'm patient - more like I'm being forced into it. :) Besides, a few things are out of my hands before it can be completed. :)

The only fires I have see with Lipos were when the person was using a NImh charger and overcharged the Lipo. Do not charge each cell over 4.2 volts and do not go below 3 volts. I normally keep mine above 3.2 to 3.5 just to be sure. Letting the voltage go too low can shorten the life of the Lipo.

Have you considered using Deans Ultra Plug connetors? They have low resistance and can handle short burst of up to 100 Amps in RC racing.

Andersons are the standard in EV apps. I went with 45's instead of the 30's recomended. The only difference is the crimp size. Nice taste in bikes. The Wahoo would make a great Ebike.

Hi jethro,

My setup is pretty similar to yours (I am planning to have up to 8 lipo packs though (6s 5ah). Do you find that storing the batteries on top of the rack makes it way too heavy in the back with a COG that is too high?

I am leaning towards putting the batteries into the panniers so that the weight is above the axle instead of above the wheel.

If you look at the pictures you'll see the panniers that I had the packs in. I was destroying them. The COG was better but it was only a matter of time before I would have dumped the packs on the road. If you go that way I suggest that the packs be clamped to a rack frame with the panniers just as a covering.
Build 1.5 is adding an Xtracycle kit, I hope to mount the ammo box behind the seatpost. I may modify the box like this.

http://i1133.photobucket.com/albums/m596/hessejef/BattBox.jpg

So that it fits over the top white truss just behind the pedals shown below.

http://www.xtracycle.com/media/catalog/product/cache/1/small_image/400x200/9df78eab33525d08d6e5fb8d27136e95/f/r/freerad-base-stright.png

I won't get this kit until Mid June so it'll be a while until I know how it fits.