Battery board design

[riba2233]

I'm not in the market for selling cells. But this is the latest and best battery chemistry, no doubt about that. If they weren't, Tesla would use something else.

You must understand that it's not easy to do life cycle test, and even more calendar life test. But my friend any I are working on a cell cycling device, so we should get some tests.

 

[Freshair]

Well you shouldn't solder anyway, you can spot weld or have someone spot weld it for you.

What I should have said is would rather a mechanical connection for ease of use and service down the road.

You must understand that it's not easy to do life cycle test, and even more calendar life test. But my friend any I are working on a cell cycling device, so we should get some tests.

Would be interested in seeing some tests.

So far everything that I have researched points towards lifepo4 being the best option for me, even if a lower voltage, seems most electric longboards coming out are built with lifepo4 as well. But if these 25R's can get at least 1000 healthy cycles in without crapping out on me or losing their power, than may consider spot welding a pack together. Otherwise am just not into replacing and rebuilding battery packs every year.

 

[Vanarian]

Fresh is there any news on your research ?

In 5 days I will have spare time, want some help to try out designs ? You can use test batteries dummies put inside a ignifuge box you put it either on a washing machine or a dirt bike you power the batteries on with data log while stressing them both in power and shocks from vibrations and if the cells successfully survived all of this, voila !You got solderless reliable battery pack design.

Or even better put them to test in a RC car like a buggy or stiff road car and bash it. This should prove enough foolproofness of casing?

 

[Freshair]

Bit of a hold on things at the moment, my young stallion fractured his patella a week ago and have had to put the money that was going towards this project towards his care.

Am interested to see how onloop did his battery pack, as apparently it is solderless and serviceable. To be honest, once funds are available again, may just pull the trigger on one of them....than I can reverse engineer it if it is a good design. Shhhh don't tell him I said that! hahaha

Am still not sure on the battery chemistry that I want to work with either, lifepo4 cycle life and safety record is pretty nice for a setup that will be fast charged up to two times everyday. Do not have a gas vehicle anymore and don't plan on getting one, so am trying to build something that I can commute on up to 10km per day if necessary, and even more if I bring spare batteries with me. NCA chemistry is looking like a decent choice as well and would be far lighter and cheaper to make, possibly cheap enough that going through a pack a year may be just as cost effective as lifepo4.

Am still pretty interested in making a connection with springs in the middle, with copper wire soldered in the middle of the spring to take the amps. This wire that runs between the spring would also make it easy to hook up a bms.

Good idea for testing them, though I think the ultimate test would be on a deck riding over an old road where the aggregate is poking through. You know when you get that vibration that makes your feet uncomfortable? Those are the vibrations I would be worried about.

Than there is the option of going with bigger lifepo4's with screw terminals, which makes life real easy, but also makes life bulky and heavy.

Ahhhh decisions decisions!

 

[Hummina Shadeeba]

Stalion?! maybe you can just ride him everywhere.

I'm still wishing someone would make a giant aluminum battery that could also serve as the board. that would be maybe easiest. Maybe way hardest.

 

[Freshair]

Horses are awesome, but for convenience of travel in todays world they are a bit too old school as nobody has hitching posts anymore....and a little harder to maintain as well.

 

[torqueboards]

His pack should be spot welded packs, I think.

 

[Freshair]

His pack should be spot welded packs, I think.

"NOTE: This battery is also actually serviceable, you can remove any faulty cell and replace it, the individual cells are really cheap and readily available for $10-$15"

Just assumed based on this statement. Suppose buying batteries with tabs spot welded on already makes it serviceable.

 

[Vanarian]

Well some people buy a Mustang, you've done better and breed your own!

Cheers up for your stallion care.

BTW this is not directly related to solderless but I've decided to use BMS, balance charging still requires too many steps when you want to balance charge your cells and chargers are bulky!

I think this should never be more complicated than "plug it and leave it" ... a bit like a smartphone or a computer, these days when the battery is full, the charger just stops charging or bypass the battery.

Normally a good BMS should be smart enough to provide that easiness, yea?

EDIT :

Look what another member did just realize
http://www.thingiverse.com/thing:820139 Pretty sleek isn't it?

 

[Freshair]

Thanks brother!

Yep, I like the battery charging for dummies option of using bms as well, like a computer or phone.

Pretty slick what you can do with 3-d printers!