Possibly new Idea for optical bay... Custom second battery modded/wired into stock?

I was just thinking what would be more useful for me than a dvd drive and I thought... A larger battery of course! I dont know what would be involved in such a mod, but I work in a building with a company that rebuild battery packs. I know there are chips and sensors and what not in the stock battery, but it it could be modded before the battery circuitry I wonder if it could be made to function as a large single pack? I think you could probably fit another half a battey in the space used by the dvd. It might not be possible or worth the cost, but in my mind I can see a properly manufactured battery set that replaces the dvd with a custom pack wired into to halves. it would make for a sweet factory option for the R3 should dell decide we for some reason still need the option of an internal optical.

..just a thought.

 

It can be done, if you can get that company to make you a longer pack of the same voltage. You would need to mod the case a little bit by removing the "wall" between the dvd drive and the stock battery location.

 

I think we would also need a microcontroller to enable the second battery charging only after the first battery is charged (not to overload the power brick)(possible problems with differing voltages). Or a current limiter before a parallel connection of the two batteries. But then I think you would need a modified BIOS,.... hard but not impossible. Definitely we would need to work like a team (some programmers, electrical engineers,....).

 

yea, wouldn't be "easy" unless you made one single custom batt to fit the area. which i dont think would be cheap at all. many challenges would arise with a second batt. number one top of the list would be that the second batt would have to be a different mAh rating. this would cause all kind of charge/discharge issues along with voltage reporting issues.

like doniGforce said it would require some custom circuit programming for the secondary batt to work correctly.

if money is no object im sure you could find a company to take on the task for the custom single battery fabrication. but for the second tandem battery idea.. its almost not even worth entertaining...

IMO just get a second M11x/M14x Batt from Dell. then when you get in a pinch just hibernate the laptop and quickly swap batteries. that what i did.

 

Thats if you make a secondary battery to fit. But if you just take the current battery, add some more cells to it you could end up with a pack with the same voltage but a higher mah rating. There would not be a need to for extra citcuits for it then.

 

it's not that simple because lithium-ion batteries are charged through a predefined process (constant current, saturation,...) (non-linear graph), and it's calibrated for that particular battery (not just voltage), changing the battery properties changes that and messes the process.

 

hmmm... well, looks like some extra custom parts would be required then.

 

I don't know, if enough people are willing to help then maybe we could try something because I like the idea too.

 

Why add extra cells? 100% increase in battery life is still very respectable. Plus, it keeps things very simple.

If you can reconfigure the cell arrangement of a second battery to fit in the same space as the ODD, then you could use the same circuit board the battery comes with.

It seems to me the easiest solution would be to find the battery connector female and male parts and make a splitter switch. Connect one end to the mobo and the first battery. Then, connect the ODD battery's connector to the same switch. Maybe get a low profile slider switch.

Then, when you charge, you charge one battery and when it's full, flip the switch to start charging the 2nd battery.

When you're using the batteries and drain the first one, put it into hibernate mode, flip the switch and wake it up to a freshly charged battery.

There would be a momentary cutoff when you flip the switch, so I don't know how Windows would react if it was fully on when you flip the switch.

You can flip it during charging though because it gets its main power from the AC.

Sounds like a sweet project, don't forget to document it with lots of pics or even better...video!

www.mouser.com is a good place to get parts for projects like this.

 

I'm please to find I'm not the only one who thought this was a good idea. Unfortunately after talking with someone who builds custom LI batteries It I was told it would at minimum require reprogramming of the control chip to allow a higher full capacity. due to the pack as a whole being chipped in addition to each cell having thier own chip simply adding more cells would not allow more capacity as they would not charge.
I like the idea of a reconfigured 2nd battery to fit the ODD, problem is some of the battery wires are signal wires that cant be merged. still I wouldnt be to upset to have open it up and swap battery plugs when the main dies. I did leave the guy with a dying pack from my r1 in case he had any other ideas or thought of someone who might. ill update this tread if i hear anything more, but it sound like the development cost would be so high it would cost a lot more than we would want to pay unless it was picked up by an oem or something.
Makes me wish I owned a battery manufacturing company. Im sure if a properly designed oem quality split pack went retail it would sell.

 

wow, really nice idea, I'm thinking I can design an internal switching circuit to switch the batteries when they're charged. If somebody can cram the same number of cells and with the same specs in the ODD space and by any chance find the chip of the original batteries (Samsung) (dead batteries anyone).

 

I don't see why you'd have to merge, ie, splice together any wires.

Just go to Mouser Electronics - Electronic Components Distributor or DigiKey Electronics - Electronic Components Distributor

Buy 2 x female connectors for the battery.

Buy 1 x male connector for the motherboard.



Buy a toggle switch that has 8-10 contacts on each side (it looks like the battery has 8-10 wires).

Solder everything together.

Test it and make sure the toggle switch works.

Then, disassemble the 2nd battery and reconfigure it to fit into the ODD bay.

Mount toggle switch onto chassis.

Profit!

It's totally possible to do this.

 

An extra battery? That is sick, I never use my ODD anyway.

Let us know if you try it