Hi Guys.
Does anyone know where the SP140 battery outer shell came from?
I’m battery building for a different application and need to jig the shape a bit. This container material looks nice and modular from the pictures - or is it a custom extrusion?
Any guidance or finger pointing in the right direction appreciated.
It’s a custom extrusion that we designed.
The 1/2 size (2kw) battery has some extra room in the case if you are looking to add to it.
Can i buy only a bat.box without battery? Need two pieces 1/2 size.
Thx
I would also be interested in getting the shell casing for the battery case.
I am thinking about buying an SP140 and I have some spare 18650 cells from my electric bicycle build and would like to build a second light weight battery with them for my future SP140.
Regarding the battery shell, I see that it’s totally enclosed and it’s also black. If overheating can be an issue especially in the summer how come it doesn’t have some holes for the air to move inside? Is it because of the outside moisture if you go through a cloud or fog?
I’m asking because, besides using plastic cell holders that let 2mm between cells, so I won’t have them wrapped in anything, I want to make my battery case out of 1,5mm aluminum sheet, with fiberglass and resin on the inside for electrical isolation, and air intake holes with coups to force the air inside and also with reverse coups to create vacuum and pull the air outside.
I might need to close and isolate this battery shell for winter flights, being made out of aluminum. Is all this unnecessary? Will aluminum be good to make the battery shell?
I would prefer aluminum - faster heat dissipation. Better fire protection just in case, no pun intended. I would not want large openings in the case, in the unlikely event of a fire it, directing flames in an unwanted direction. But not air tight to allow a some type of emergency expansion venting, IMHO.
Cheers
hi, some hints: the battery box should be tight to avoid pollution with dust from the air. dust can also attract water!
in any case, a pressure equalization valve is necessary, which in the worst case can release the pressure from the box. some manufacturers use one-way valve stickers or bronze pressure outlets as is known from pressure regulators in compressed air.
with housings made of stainless steel or aluminum, condensation forms more easily than with hard plastic or fiberglass.
many variants are possible, there is no right or wrong, it depends on the purpose. i personally prefer fiberglass kevlar carbon hybrid material. for some other applications, stainless steel / titanium is ideal for me.
in general, in e sportscenne, hard plastic with a high fiber content has been the most widespread. E-Bike, E-foils, E-Motocross etc. Sometimes combined with metal surface plates to reinforce. just as often only edge protection made of metal.
I would say that is more for cost saving than anything else.
Cheers
Hmm…didn’t know that moving air can do harm by bringing dust and retaining moisture afterwards! Boomer… 
. I was sure that moving the air between the cells will be great for them… Well then I’ll benefit of the aluminum capacity of dissipate heat and regarding some sort of valves I think that a few round holes on the sides, so not towards the pilot, and covered with some soft stikers.
During the winter I might make some isolation covers for the battery case if the probe thermometer in the middle of the pack or the flight duration will show me the need.
As for condensation I think I’ll keep a huge nilon sack at my appartment door, for when I fly in winter, to cover the entire paramotor main frame with engine, esc etc before bringing it inside. Can’t think of any other method of bringing the paramotor from snow to the appartment and avoid condensation. At least the motor bearings are very exposed.
Oh…and yes I went for aluminum to add a degree of safety in the house and air. And I will charge and store it in the bathroom the most non flamable place in the appartment. Although kind of high humidity but it will be in the nilon bag. Can’t think of a safer option…I’ve been charging lipos in there for years, keept in an ammunition metal box with compartments and presure release holes it’s like a bunker!
I was thinking of asking on the forum just that, where do appartment flyers keep and charge their batteries?
an example: if you want UN 38.3, the cas must have a certain strength and must not deform permanently, for example. Aluminum is therefore generally ruled out when it comes to “real” certified batteries. with diy it is of course completely different, everything is allowed here if you can take responsibility for it yourself.
but it’s true with cheap plastic it’s very cheap if you have thousands of pieces. in the case of high-end plastic in small series, plastic is extremely expensive for mold construction and the machines for production are expensive to set up.
My tip regarding heat dissipation: build a system that never has problems with heat. That is, build the battery so large that it cannot get too hot purely from the cell load. your battery will also give you pleasure for a very long time. if you have to cool the battery, it is certain that it will not last long because the cells in the core can never be cooled and therefore lose performance more quickly.
That would require at least 3 Parallel packs to split the current load. Not practical for foot launch, a trike yes.
cheers
I’m talking about foot start eppg systems. I am sure that more than 50 pilots worldwide confirm that around 3 to 5 kilowatt hours from the battery are completely sufficient without having thermal problems. high-performance wings and eppg´s make it possible to fly with 2 kilowatt batteries without any problems, even packed in foam and insulated.
If you compare ultralight aircraft or other heavy projects with eppg foot launch from the motor power profile, there is no point in discussing them here.
I do have a tendency to look at what would be needed to get heavier things up off the ground.
So what is the average battery configuration (voltage, series/parallel) being used out there for foot launching today.
I look at the SP140 3.7kwh battery think I would need 3 of those in parallel to get some decent time in the air on my single seat Delta wing trike. I could not find a posting on how these are truly configured - one post by Bob speculating 24s11p?? Which is good configuration to keep the cells from too much overheating…I guess😁
Cheers
I know they mainly use more efficient Wings like ATOS, but look at the Ant-E trike. I believe they use the German Geiger Engineering motors and batteries, and are doing well.