Li- Mods?

[abigsmurf]

I've been looking at various forms of batteries for the GP2X to alliviate the 3-ish hour battery life and have been looking at doing an ultra basic mod using Lithium ion cells.

I've got some questions: I've seen a voltage regulator that would let you get a constant 2.85V @ 0.7A from a CRV3 cell. can a CRV3 cell possibly fit into the battery case (even if some light filing is needed), how efficient are voltage regulators (ie, would I still get enough mah to make it worthwhile) and would I likely blow up the battery and the console?

 

[green1152]

I've been thinking about this as well, it'd be nice to be able to do some iPod or psp style thing where you just hook up your gp2x to the wall and let it charge for a bit. Although I'm not bothered too much by batteries, because you can always get backups.

 

[thejoeandchip]

I've been looking at various forms of batteries for the GP2X to alliviate the 3-ish hour battery life and have been looking at doing an ultra basic mod using Lithium ion cells.

I've got some questions: I've seen a voltage regulator that would let you get a constant 2.85V @ 0.7A from a CRV3 cell. can a CRV3 cell possibly fit into the battery case (even if some light filing is needed), how efficient are voltage regulators (ie, would I still get enough mah to make it worthwhile) and would I likely blow up the battery and the console?

​

well, voltage regulators turn a bit of the energy in to heat. this waste energy and can cause harm if not well vented, though that usually isn't a problem. you might wanna check to see if the gp2x can take 3v because i beleive that it can and will help with lcd problems and movies crashing. If not, your best bet is to get a custom battery pack built. It cost a lot but enough nice cells in parallel and you will have insanely good battery life. Here is a good place for that http://www.robotcombat.com/marketplace_bat...pack_build.html . IF you go the battery pack route then i recommend you give up on making it fit in the battery case. instead, try making a cool case extension, so it would kinda look like the psp hard drive or any other of the million psp add-ons.

 

[Radek]

I've been looking at various forms of batteries for the GP2X to alliviate the 3-ish hour battery life and have been looking at doing an ultra basic mod using Lithium ion cells.

I can not help here but given that LithIons are more costly wouldn't be sufficient to buy another pair of NiMH (or even more)?

For me a two sets of NiMH 2100mAh are (more than) enough for a day (and I'm recharging them at the night).

 

[Ranma13]

http://www.mtekk.com.au/browse/page1091.html

Read this site for more info on why Li-Ions are impractical as a power source for devices not specifically designed to take them.

 

[Hanz™]

Somebody did a mod like this for the GP32, can some one find that? I tried to bump it to draw attention to it a while back but I don't think it was appreciated and I think my post was deleted or something as I cannot find it - it was in the GP32 news section.

Edit: Here it is. Devour: http://www.gp32x.de/board/index.php?showtopic=11943

Can someone tell me the size of the GP2X battery compartment?

 

[Michael]

uh... big enough to hold 2 AA batterys..

 

[DaveC]

How about using the pack from the Xbox 360 wireless? That pack fits in place of the 2 AA batteries. The catch? You need an xbox 360 to charge it

 

[Michael]

hmm... show a pic. That sounds intresting tho.

 

[Hanz™]

How about using the pack from the Xbox 360 wireless? That pack fits in place of the 2 AA batteries. The catch? You need an xbox 360 to charge it

​

What is the voltage and mAh, and also what is the relation between mAh and volts I have forgotten?

 

[DaveC]

How about using the pack from the Xbox 360 wireless?  That pack fits in place of the 2 AA batteries.  The catch?  You need an xbox 360 to charge it 

​

What is the voltage and mAh, and also what is the relation between mAh and volts I have forgotten?

​

Power=Voltage x current.

 

[Hanz™]

How about using the pack from the Xbox 360 wireless? That pack fits in place of the 2 AA batteries. The catch? You need an xbox 360 to charge it

​

What is the voltage and mAh, and also what is the relation between mAh and volts I have forgotten?

​

Power=Voltage x current.

​

Does that mean that if a battery supplies a large voltage and you regulate the voltage it supplies you can get a larger mAh out of it?

 

[Muncher666]

DD mod for gp32

Waiting on my gp2x at the moment, but could something like this work as well? (a bit bulky I know, but it's a thought)

Allan.

 

[Reaperman93010]

Does that mean that if a battery supplies a large voltage and you regulate the voltage it supplies you can get a larger mAh out of it?

​

it depends on how you do it, but yes, you can.

as mentioned before a linear regulator will shed the extra voltage as heat. But a switching regulator will not.

The GP2x may have something usable inside it along those lines already. It's entirely possible that it will take the 3.7 volts, but I'd hate to be the one to try it. It seems to run off a fairly wide variety of voltages, but I'd hate to be the first one to fry my 2x.

 

[Hanz™]

Does that mean that if a battery supplies a large voltage and you regulate the voltage it supplies you can get a larger mAh out of it?

​

it depends on how you do it, but yes, you can.

as mentioned before a linear regulator will shed the extra voltage as heat. But a switching regulator will not.

The GP2x may have something usable inside it along those lines already. It's entirely possible that it will take the 3.7 volts, but I'd hate to be the one to try it. It seems to run off a fairly wide variety of voltages, but I'd hate to be the first one to fry my 2x.

​

Didn't Reesy say something about running his at 4.5v?! hehe

I think it would probably take 3.7V fine - I remember the GP32 used to take 3.5V fine.

I think our best bet would be hoping that someone like ED or craigix could get some custom made battery packs by nexergy or something - I have been searching for absolutely ages.

Edit: WOW! 3000mAh non-rechargeable batteries. They are called: Energizer e2 AA Lithium

I wonder if either of these could fit round the back, and whether with a voltage regulator etc... anything could be done:
http://www.budgetbatteries.co.uk/product/2...0_1Mar05_212737
http://www.budgetbatteries.co.uk/product/2...0_1Mar05_212737

CRV3 will be our best chance and aparrently they will fit into all AA compartments unless the compartment is a figure of eight shape (don't ask me how that is possible).
Interesting read.

What is the best crv3 battery I wonder, the kodak ones appear to be 3200mAh at 3v and according to that article I read it should last longer than something which is 3200mAh at 2.4v, unfortunately these ones are non-rechargeable?

Diemensions for a crv3 are:
51.90 x 38.40 x 14.20 mm

They will definetely fit but if there is a seperator it will need to be broken.

These seem pretty good.

 

[abigsmurf]

Power=Voltage x current.

​

Gotta remember to use every measurement type featured in the original figures when working out what something represents ^_-

potential energy = voltage x current over time

 

[abigsmurf]

one thing I've discovered, Li- polymers don't explode when shorted or overcharged like regular Li-'s. That would make experimenting a whole lot safer for me (if not the gp2x)

 

[OMars]

This one seems rather nice..........