Quick release battery pack

[zeropointbug]

I searched the couple old threads on quick release packs and trays, there was one good idea from 'shizzon', but entirely unfeasible for most, for me.

I was thinking why not use a PRE-MADE battery pack case like a dewalt 20v/3.0Ah lithium pack, place my 6s/2200 pack inside (if fits) and somehow find both the drill side or charger side of the mechanism to mount on the RC. A guy would have to figure out how to integrate a Deans connector into the system, which might not be hard at all. The only real 'BUT' is getting a hold of some EMPTY dewalt battery cases, or finding faulty/bad packs on ebay.

If this could be done, then battery changes would be as quick as a refueling for a nitro RC.... this would be huge make up time in a 30 min main race.

Let me know what you guys think, and if you guys know where a guy can get some of these dewalt pack cases (or whatever brand), as long as it's strong enough for the job.

[_paralyzed_]

even easier, just mount a charger on the chassis, with leads going to the esc instead of the charging circuit. Installing a battery would be as easy as putting a battery on the charger

i cant help on the drill pack cases...in my mind is a tray screwed into the car which will take a smaller tray inside it which carries a lipo and deans...or 2x bullets 4mm...so its kwik change. as you drop the tray in the connectors line up and engage...the trays could be some perspex or machined nylon.
something light anyway...hmm carbon fibre...

maybe held in by 2 velcro straps or some clips...
chris

[zeropointbug]

Paralyzed, yeah that's exactly what I mean mount the charger side, with some plastic trimming, just the locking mechanism.

Chris, I would love to do some custom battery cases and tray, and it would be the most ideal way to go, but that would cost alot of money;

I would mount it so the battery change can occur from the side of the vehicle, without removing the body shell. I come in for a pit stop, pull up the side of the body grab the pack off, throw on another one, boom boom, just as fast as a refuel on a nitro.

i don't really see much fabricating work in getting the lipo packs in the drill cases, I do see a bit of a engineering matter for the esc/RC side of the pack mounting. I don't see an issue with mounting a deans or some sort of easy sliding bullets in the lock, just getting them to lineup.

Where to get empty drill pack cases?

Hello

I know you have said you don't want to have a custom case, but quite honestly I find the drill battery case bulky in most cases. Their square shape would also make it hard to find RC lipo's to stick inside?

I did some very rough designs quickly of what I would do in this case. The bottom tray would be made from 1" delrin (Offcuts from big companies can be had for cheap on eBay), and milled out, couple of holes drilled, press/glue in your male bullets, probably take all of 30minutes depending on how big an endmill you use in the delrin. For the batteries you simply make a little delrin block housing the female bullets and would then be soldered on to the lipo wires. The block would probably require some hot glue/silicon and then heatshrink over the both it and the battery to be rigid enough with a soft pack lipo. Hard pack lipos mostly have the bullets already so no need for the block.

Problems with the design would be you still need some sort of strap to hold the battery, but something could be designed there quite easily I'm sure. Also for the best possible alignment when inserting the battery should only just fit in the tray. That means if you use different capacity batteries regularly, it probably won't work too well. That said if you only have one type of battery, doing the mill work yourself, it would probably only cost about $30-50 in material depending on how many batteries you want to 'convert'?

EDIT, looks like chris mechanic beat me to it!

Interesting idea, I shall be watching to see how you solve it

Kieren

[pinkpanda3310]

How about utilizing a hardcase lipo? The ones with removable leads - http://k007.en.ec21.com/50C_5700mah_...6_4252618.html

[zeropointbug]

Aussienerd, that is the ideal system if I had the right shape lipos, some good delrin plastic, and some sort of locking system would be nice. Although it might be easier to make it a parallel slider vs. adjacent straight in, for alignment reasons.

The packs I have are Hyperion 6s 45c 2200mah packs, they are 105 x 34 x 53mm dimensions, so they are pretty short and stubby, just plain small... good for 10 mins runtime on my track with still ~20% SOC left. These things are awesome, wicked power, good handling from the light weight, and surprising super cool temps.

http://www.aircraft-world.com/shopexd.asp?id=3097

I would think they would fit inside this dewalt case, but I will have to maybe check it out at a hardware store, do a rough fit measurement.

[rawfuls]

I like Pinkpanda's idea, hardcased with bullet internals.

I'll be honest, I didn't read much of the thread... so not sure if you threw it out already, but..

You would mount the bullet connections on the chassis, and pull straight up if you wanted the battery out, push down to mount.
To lock, just a velcro strap, or a twisty metal mount (imagine a C, the cutout on the bottom, held in by a screw somewhat tight but still moveable, like a pivot, then pivot the clamp over lipo).

[zeropointbug]

Yeah, that is the most ideal solution. Plus having a regular wire lead with deans on it as well for charging. I was just looking at the traxxas XO-1, and couldn't help notice the awesome battery trays! One retainer latch per tray, just a simply squeeze of the latch and boom, the hold down comes up.

I wouldn't mind using it, if I would be able to plug/unplug the pack leads without taking the body off. (well my pit guy) This way should yield pack change times of maybe 10 seconds? I can live with that!

Let me know what you think.

i've thought about this too... but a bit simpler

2 male bullets poking up out of the bottom of the battery tray... push your stick pack onto the top of them... no fiddling with wires and all the wires are hidden under the plastic :)

I will be doing this with my axial exo... as getting wires in through the holes in the cage will be a nightmare!

[rawfuls]

Originally Posted by Bazzokajoe

i've thought about this too... but a bit simpler

2 male bullets poking up out of the bottom of the battery tray... push your stick pack onto the top of them... no fiddling with wires and all the wires are hidden under the plastic :)

I will be doing this with my axial exo... as getting wires in through the holes in the cage will be a nightmare!

Hehe, that's what I meant, just didn't know how to simplify it..

[pinkpanda3310]

I never knew how adjustable the battery tray is on the XO-1, nice.

Rigging a car to change batteries without removing the body would be difficult in my mind. The first method that sprang to mind was the battery slid into the side of the car somehow to minimize opening the body.

The second method that sprang to mind would be to cut a trap door in the chassis for the battery to load/unload. That would require a lot of thinking to get it right and would also comprimise some stuff like chassis strength and possible battery ejection etc...

One more method that just came to mind would be to operate on the body. Asthetically this would look aweful but if lap times are more important... cut down one side of the body (right above the battery tray), strategically place some fibre glass tape to act as hinges, use velcro to hold the body in place against the side guard. I think you might need more space to work with though.

Hope these idea's help your train of thought.

[pinkpanda3310]

Now i've slept on it I got more idea's, but maybe not suitable. Since this is for racing I'm guessing it's a SCT, buggy or truggy project?

The idea I had was if it was a maxx with a slightly higher chassis plate just mount the batteries on the underside of the chassis (with a little extra protection of course). Or if the car had tvp's (I know the savage is not the racers choice) just flip the battery tray upside down.

If you could make a custom chassis plate - make one side normal and the other side make it wider then bend it up and across so the battery tray can be mounted underneath and sit flush with the rest of the chassis.

Alternatively use the stock chassis plate bend up one side and mount the tray to the vertical edge like a tvp i.e. savage bat tray mounted upside down. I reckon that's my best idea yet

[zeropointbug]

This is for my racing Revo if you didn't know, check my other thread, racing battery choices.

panda, you hit everything spot on with the limitations. Body cannot be removed, that takes up alot of time. Battery cannot be changed/swapped from underneath, because of the skid plate I have, and for other obvious reasons, like damage. There will be either a trap door on the body like you said or simply just flex the shell upwards enough that you can do what needs to be dont, but that might two hands, so I will try it without modifying the shell first, then, if need be...

Only question is will the mounting on the XO-1 battery rays work with me so I can rig it up to my truck.

[pinkpanda3310]

Ooh. Looking at your revo I'm wondering if there is enough room to use the xo-1 tray. I think you're probably better off with your original idea of quick release connectors. Having the battery mounted on edge will be an advantage for side access.