Lithium Ion battery for the E/X-Mag?

[Levi]

The driver on the board is more than capable of handling more current, so a lower voltage solenoid at the same wattage is just a drop in part without any additional circuitry.

Considering that its AGD, I figured it was significantly overbuilt. But I try to never assume without verifying.

I think you're on to something here.

Hmm... this thread make me wish I had an emag or xmag to tinker with... too many more mags and the wife might start asking questions.

[rukh013]

Considering that its AGD, I figured it was significantly overbuilt. But I try to never assume without verifying.

I think you're on to something here.

Hmm... this thread make me wish I had an emag or xmag to tinker with... too many more mags and the wife might start asking questions.

Ha, sounds like my wife

If the 22v battery pack fit in the emag pack, wouldn't we just need to change the connections to the board?

[athomas]

The 22V packs are slightly different dimensions than the emag pack. Other than that, any pack can be made to fit the existing emag pack connections.

[Justus]

Would going with something like a 22v lipo pack make the thing lighter, and could there be something made with it to make it a drop-in replacement for current Emag batteries and work with current packs (meaning, all you would need besides the new battery is a charger, and all those custom milled battery packs wouldn't be going obsolete?)

[athomas]

The LiPo pack battery rating to get the same rating as the Emag is the 5 cell pack which would be a 18.5V rating. The 6 cell pack gives a 22.2V rating which would be quite a bit higher than the emag battery. You would need to change the solenoid to use this pack.

The LiPo packs are typically lighter than equivalent mAh packs made from NiMh cells. The dimensions are slightly different though. A 5 cell pack, which is closest to the emag pack rating so that you wouldn't have to change soleoids, is an odd size. You either have a really long skinny pack, or a really fat short pack, or a 3 + 2 pack. I would use a stacked (3 on top, 2 on bottom) 600mAh series pack. It will fit into the existing emag battery pack with room to spare and will be less weight.

[Justus]

Is there a battery pack like that on the market right now, or are we in "custom" territory? I'm putting a lot of search terms through Google but coming up empty when it comes to a pack like you're describing...

[athomas]

Is there a battery pack like that on the market right now, or are we in "custom" territory? I'm putting a lot of search terms through Google but coming up empty when it comes to a pack like you're describing...

Yes and no.

The individual cells are available that will allow you to put together the configuration you want. The packs are available through anyone who builds custom packs. The 600mA cells are approximately 70mm long x 20mm wide x 7mm thick. You can make your own arrangement using a serial connection of the batteries. You can even add a balance connector so that you can keep the pack together and balance charge them properly without having to charge the cells individually.

I think the smaller ones are often referred to as nano cells.

[Justus]

I really don't know anything about making custom battery packs. But if a pack could be made that is significantly lighter than the standard NiMH pack, I'd be very interested. Anyone interested in taking the bull by the horns and seeing if this can actually happen?

[mostpeople]

I've got 2 dead packs now, so I'm hurting as well.

I think its clear we are in custom territory on this one, however there are many options for groups that build custom battery packs.

The questions become:

1. Do we want NiMH? Or do we want LiPO?
2. What are the "No Kidding" Operating limits of the xmag circuitry? What is the ideal battery output?
3. Do we want a drop in replacement for all battery housings? Or do we want a new battery housing as well?
4. If you go LiPO how are you going to charge it? (I was thinking a hole in the bottom for a charging plug?)

Food for thought..

[athomas]

1. Do we want NiMH? Or do we want LiPO?

LiPo has more capacity for the size, so it will always be the smaller, lighter option.

2. What are the "No Kidding" Operating limits of the xmag circuitry? What is the ideal battery output?

The circuit board itself is quite robust, although I can't look up the specific limits because my emag is packed away for a change of address. The solenoid is designed to operate at a specific voltage in order to draw the correct amount of current to develop the required power needed to consistently work properly.

3. Do we want a drop in replacement for all battery housings? Or do we want a new battery housing as well?

This is a possibility for both types of packs.

4. If you go LiPO how are you going to charge it? (I was thinking a hole in the bottom for a charging plug?)

You could put the charging plug between the two top contacts, in the bottom of the pack (it would be easy to change the bottom piece), or on the lower back of the pack inside the groove (where it would be protected, but would require some machining).

[Justus]

My opinion and reasons:

LiPo pack for lightweight. A NiMH pack is what we have already, right?

Needs to be able to drop-in to current battery housings. If not, then people with finished custom (anodizing, milling, or both) or original restored Emags and Xmags won't be customers. A secondary option of a new battery housing isn't a problem, but backwards compatibility is a must.

It would be better if the battery pack could be taken out to be charged, that way a person could have two of them, keeping one as a backup. Then if they forget to charge it and it dies, they don't have to sacrifice their battery housing to charge the battery. Instead, they can take it out to charge it and pop the fresh battery back in and keep going.

[mostpeople]

I am on the same page with you Justus, backwards compatabity is a must.

Ideally though, we could charge a new battery with it still in the pack, making it easy to use.

Let me do some research on this one. What I don't have and need to know is the board and solenoid specifications.

[Justus]

What I don't have and need to know is the board and solenoid specifications.

How are those acquired? I can take off my grips and read any of the numbers you want, if that will work. Maybe even provide a high-res photo?

[absocountry2]

This place can build custom packs. My emag pack has 14 AAA batteries. It would cost $42 to get a duplicate pack made. The only difference would be 14000 mAH instead of 650. Should just last longer

http://www.cheapbatterypacks.com/custompacks2/CustomPacks.aspx?mid=20

[athomas]

This place can build custom packs. My emag pack has 14 AAA batteries. It would cost $42 to get a duplicate pack made. The only difference would be 14000 mAH instead of 650. Should just last longer

http://www.cheapbatterypacks.com/cus...ks.aspx?mid=20

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.