Mounting options for lipo pack

Batteries, Chargers, and Battery Management Systems.
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tostino   10 kW

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Mounting options for lipo pack

Post by tostino » Jul 04 2017 9:05am

Hey all, I am looking for some advice on mounting my 6s 16ah multistar packs to a rigid mountain bike frame. I have 6 of them for a 18s 32ah pack.

I was really hoping to mount them in the triangle, but it seems like i'm running into issues with that. I ordered a triangle bag from Lunacycle, and it came in with some really messed up tolerances. The two sides of the bag are noticeably not the same size. Regardless of the quality of the bag, there is absolutely no way those packs would fit in that bag. I could fit 3 of them, 4 would have fit if the tolerances weren't messed up. Obviously that won't work.

What are the other mounting options you guys have seen / used? Are there any much larger triangle bags you know of?

I'd really prefer to keep the weight centrally mounted if possible rather than having them hanging way off the back.

Temporarily I have them stuck in a backpack... but that's not an ideal location because these things are really heavy. Starts to hurt my shoulders from the weight after ~15 min, which is nothing when you have a pack this size.

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danielrlee   1 kW

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Re: Mounting options for lipo pack

Post by danielrlee » Jul 04 2017 9:14am

I managed to fit 6x 4S 16Ah Multistars in an EM3EV triangle bag, mounted on a 16" Kona Blast hardtail frame, but it was tight. I was limited more by the frame size than the bag, but I'm not sure it would have stretched to 6x 6S packs with a larger frame.

How about putting 4x packs in the triangle bag and the remaining two in a top tube bag? This is similar to my battery arrangement as I also have an additional 4x 6S 5Ah Turnigy packs in a top tube bag, which sits over the triangle bag.
Last edited by danielrlee on Jul 04 2017 11:22am, edited 1 time in total.

zackclark70   100 W

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Re: Mounting options for lipo pack

Post by zackclark70 » Jul 04 2017 9:16am

half in backpack half in the bag you have maybe as a temp solution

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motomech   1 GW

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Re: Mounting options for lipo pack

Post by motomech » Jul 04 2017 11:26am

tostino wrote:Hey all, I am looking for some advice on mounting my 6s 16ah multistar packs to a rigid mountain bike frame. I have 6 of them for a 18s 32ah pack.

I was really hoping to mount them in the triangle, but it seems like i'm running into issues with that. I ordered a triangle bag from Lunacycle, and it came in with some really messed up tolerances. The two sides of the bag are noticeably not the same size. Regardless of the quality of the bag, there is absolutely no way those packs would fit in that bag. I could fit 3 of them, 4 would have fit if the tolerances weren't messed up. Obviously that won't work.

What are the other mounting options you guys have seen / used? Are there any much larger triangle bags you know of?

I'd really prefer to keep the weight centrally mounted if possible rather than having them hanging way off the back.

Temporarily I have them stuck in a backpack... but that's not an ideal location because these things are really heavy. Starts to hurt my shoulders from the weight after ~15 min, which is nothing when you have a pack this size.
You should be realizing by now that you put "The cart before the horse."
For future reference, or for anyone else looking at building a pack, a more sensible approach is;
1)Build/buy the enclosure to fit the donor bike.
2)Mock up perfered "bricks" out of cardboard and trial fit to determine configuration and capacity.
3)Order batteries.

It would seem to me, your only choice is to reduce capacity, as 32 Ah is needlessly large. My pack is 25 Ah(Which couled easily fit in a large frame bag)and that works out to almost 50 miles. I can't remember the last time I even came close to using the full pack, as 50 miles for the routes and speeds I travel, makes for a very long ride.
Having said that, here is how I carry 25 Ah;
100_0064.JPG
100_0064.JPG (73.17 KiB) Viewed 517 times
I carry 4) 6S/10Ah bricks in the frame bag for 12S/20Ah(12S is a much easier Voltage to work with, BTW). If I mounted my controllers outside the frame bag, I could fit 2 more 6S/10Ah bricks for a 12S/30Ah pack.
100_0076.JPG
100_0076.JPG (115.41 KiB) Viewed 517 times
In addition, I carry 2 6S/5Ah bricks in a tube on the frt. of the bike's down tube, for an additional 12S/5Ah. That would be a total of 12S/35Ah w/out much difficulty. But, with my current pack size(25Ah), the bike weighs 75 Lb.s and I really wouldn't want it to be much heavier.

How do you charge your pack?
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/20Ah Multistar Lipo rear 5Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
viewtopic.php?f=3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
viewtopic.php?f=3&t=49691&p=1378484#p1378484

tostino   10 kW

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Re: Mounting options for lipo pack

Post by tostino » Jul 04 2017 1:42pm

motomech wrote: You should be realizing by now that you put "The cart before the horse."
For future reference, or for anyone else looking at building a pack...
Honestly, not really. They're just on the current bike I have available. I can buy any other bike my heart desires that would fit them better, however the bike is not the issue, the issue is just finding a triangle bag large enough. If I really felt up to it I could make my own. I'm just busy enough that it's not really something i'm up for right now unless I have no other options.
motomech wrote:How do you charge your pack?
Right now I have 2x meanwells which power a dc-dc converter which steps the voltage up to what's required, and provides CC/CV.

I have a Eltek Flatpack2 coming in to power that same DC-DC converter which I have better FET's coming in for to handle the increased power it's able to provide.

Should charge the pack in ~2 hours.

tostino   10 kW

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Re: Mounting options for lipo pack

Post by tostino » Jul 04 2017 2:33pm

Should also add that I have a RC charger to make sure they're balanced every once and a while... though the last pack I built (a Konion 14s 20p pack) didn't need to be balanced once in the ~3 years I had it.

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