Lithium Ion battery for the E/X-Mag?

[mostpeople]

We could try a group order from them?

[absocountry2]

The pack using 1000mAh batteries would be a 1000mAh pack at 16.8V because the cells are in series. If the cells were in parallel, then you would have 14000mAh, but the pack voltage would only be 1.2V instead of 16.8V.

Those batteries are expensive. I typically pay about $1.00 per cell or lower when I buy 1000mHA AAA cells, but that doesn't include building the pack.

You are correct, thank you for fixing that. I knew better but I type numbers on the keypad and hit the one and four together. 14000 would be very impressive for AAA in 16.8v.

[Justus]

Still have a lightweight, LiPo Emag battery pack on my wishlist. Anyone with superior battery knowledge than me (read: a lot of people here on AGD) have any suggestions?

[BTAutoMag]

I love how every is excited about the possibility but glazed over my post.

[knownothingmags]

I love how every is excited about the possibility but glazed over my post.

car batteries are kinda different,(yes a battery is a battery), lipo is a different monster, even if it is a carbattery,
unless you are talking about a max amps starter battery, then you are on the right track.

[AGDRetro]

So I just started this thread and walked away, has anybody had any luck creating a drop-in, backwards compatible pack?

[2xFast]

I've got a 3 cell and a 2 cell 500 mAh pack on order (1 ea) that I'm planning to use in series for prototype purposes. I probably won't end up test firing for a month or two still. I'm going to run it through a morlock and I have to wait for that board.

The catch I ran into is that a lot of LiPo's don't have the C rating for the solenoid:

Solenoid is a S-15-75-26AD
Which if I'm reading the spec sheet right means:
Design voltage: 14.6
Watts: 80
therefore required amps = ~4-5.5 (depending on input voltage?)

The NiMH pack for reference can put out around 22A...for short periods at least.

500mAh x35 = 17.5A sustainable output, higher burst...that should be plenty to drive the solenoid and not so far off from the stock pack. 500 mAh isn't 650, but it's close and should be functional for a day of play unless I'm missing something.

What I found was that the cells that fit my needs aren't AAA shaped or even round, which means a custom battery housing is probably going to be required if you want to maintain performance AND shave weight.

[2xFast]

I love how every is excited about the possibility but glazed over my post.

I would be all over some help if the offer still stands. The specs are in my previous post. Let me know if you need more info.

[knownothingmags]

I've got a 3 cell and a 2 cell 500 mAh pack on order (1 ea) that I'm planning to use in series for prototype purposes. I probably won't end up test firing for a month or two still. I'm going to run it through a morlock and I have to wait for that board.

The catch I ran into is that a lot of LiPo's don't have the C rating for the solenoid:

Solenoid is a S-15-75-26AD
Which if I'm reading the spec sheet right means:
Design voltage: 14.6
Watts: 80
therefore required amps = ~4-5.5 (depending on input voltage?)

The NiMH pack for reference can put out around 22A...for short periods at least.

500mAh x35 = 17.5A sustainable output, higher burst...that should be plenty to drive the solenoid and not so far off from the stock pack. 500 mAh isn't 650, but it's close and should be functional for a day of play unless I'm missing something.

What I found was that the cells that fit my needs aren't AAA shaped or even round, which means a custom battery housing is probably going to be required if you want to maintain performance AND shave weight.

be carefull putting together 2 and 3 cell packs.
im sure you know what to do. but sometimes they don't play nice together, and these batteries love to start amazing fires.

[2xFast]

I'm learning as I go. Assuming the packs are ~ equal in nominal voltage it shouldn't be an issue. If they aren't terribly close I thought the only real risk was my low voltage warnings wouldn't be reliable. If I'm not getting near full discharge it seems like the risk there would be minimal and obviously I wouldn't be charging them as a single battery. Is there something else to watch out for?

It's not ideal, but it's just to verify that the cells used in these packs would work...if they do I'll try to source the cells themselves and build a proper 5 cell pack.

[knownothingmags]

I'm learning as I go. Assuming the packs are ~ equal in nominal voltage it shouldn't be an issue. If they aren't terribly close I thought the only real risk was my low voltage warnings wouldn't be reliable. If I'm not getting near full discharge it seems like the risk there would be minimal and obviously I wouldn't be charging them as a single battery. Is there something else to watch out for?

It's not ideal, but it's just to verify that the cells used in these packs would work...if they do I'll try to source the cells themselves and build a proper 5 cell pack.

not sure if what you are doing is ok,
I just don't want you burning down your house.

there are companies that will build packs for you at whatever spec you want.

I make our in house. but im not able to bring them to the public, for a lot of reasons.

best of luck keep us posted.

[need4reebs]

not sure if what you are doing is ok,
I just don't want you burning down your house.

there are companies that will build packs for you at whatever spec you want.

I make our in house. but im not able to bring them to the public, for a lot of reasons.

best of luck keep us posted.

KNM: wait wat? you make wat in house that you cant bring them to the public? im confused?

2xfast:a battery store can make you a battery for your Mag pretty cheap.

[2xFast]

need4reebs: I'm trying to make a LiPo replacement. If you can find a battery store willing to do it I'm all ears. NiMH is easy, already have one don't need another.

knownothing: Specific pitfall issues would be helpful, vague "might be dangerous" statements are not. I'm aware lipos can be risky...

[need4reebs]

need4reebs: I'm trying to make a LiPo replacement. If you can find a battery store willing to do it I'm all ears. NiMH is easy, already have one don't need another.

knownothing: Specific pitfall issues would be helpful, vague "might be dangerous" statements are not. I'm aware lipos can be risky...

try batteries plus...take your battery in with ya and see what they say or can do for ya? and if they cant/wont make ya one maybe they know where you could buy one or get one made?

[2xFast]

I've tried shopping around the RC battery places (specifically the one linked in this thread earlier). No dice. As I mentioned the trick is the C rating. Getting something that can dump enough amps fast enough requires non AAA shaped cells.