It’s a long time ago since I’ve bought MSI Wind netbook. I’m not using it very much, because I’ve bought new MacBook, but it doesn’t mater. have two batteries for Wind, one small original 3-cell and one extra large, extra cheap 9-cell from eBay. The smaller one isn’t used too much, because it can power netbook only for 2 hours (bigger one 6 and more
) . I’m very curious and I have Monome 128 and I hate it’s big ugly 12V power adapter, battery can be good choice, so I decided to open it. Spoiler: Battery remains usable even in netbook!! Video and howto after break!! If you like this idea, send link to this article to your favorite notebook manufacturer, maybe we can change actual state!!
BTW: If you like this hack, look at our iPhone controlled RC car
Parts
- USB female connector TYPE A (Sparkfun $1.25)
- Volatage regulator 7805 (Sparkfun $1.25) or fancier and cooler 78SR Step-Down (Digikey $14.01) (thanks to Max via comments)
- wires, soldering station, hot glue etc.
About & Howto
Opening of the battery case id pretty tough, I had to use even a knife
There is a lot of ICs in battery, more than I thought, but finding source of 12V power was pretty easy. Battery has even a lot of free space, good for us
Because of lots of space, I decided to add USB charging capability (for iPhone etc.) At first, I had to decide where is the right place for connectors and cut the holes for them. Three pin connector is 12V supply (scheme is +-+, so you can’t plug it wrong way
).
I found source of 12V and solder cabels on it. 5V for usb is regulated by 7805 from 12V.
7805 regulator was pretty hot, iPhone wants 500mA
We added small passive cooler, but it wasn’t as efficient as we thought. After pluging iPhone, temperature rised up to 120′C
We had to do better cooling = bigger passive. Second try cools it on 70′C. Good job!
Battery had holes in case, but they was covered by stickers. We decided to cut the sticker off for better cooling.
One more thing, close the case and it’s DONE!!! Looks like new
Full charge of iPhone 3G tooks 2hours and 22minutes. I did graph of charging so you can compare it with charging from PC Wind baterry iPhone Charge Graph
After full charge of iPhone still remains 50% of juice in Winds battery!! So you can charge twice
But I think it can be even better, if you do a more efficient PCB, 7805 wich we used has lots of temperature losts
Battery can power up Monome 128, which was original idea of hack
More photos on FLICKR.








































Vincent 7.39 on 28. 7. 2009 Permalink
The reason your 7805 is overheating is because it has to dissipate the voltage difference between the 12V down to 5V. So its dissipating 7V into heat even before it drains more current.
prusajr 7.48 on 28. 7. 2009 Permalink
I thought that, is there more efficient wiring? I took 7805 because I have plenty of them here and was easiest to work with
William Douglas 8.36 on 28. 7. 2009 Permalink
Try using a DC-DC Buck converter. They only cost ~$4 in quantities of 1. Find one rated at ~740mA output. You’ll also need an inductor – another couple of bucks. Anyway, the circuits are simple – usually around 7 components required. The efficiency of the circuit will go from <40% to ~90%.
mats 8.46 on 28. 7. 2009 Permalink
Use a switch mode 7805 drop in replacement instead.
It will give you like 85% power utilization of the battery instead of the 40% you get now. $15 instead of $0.50 gives you double the run time and a cooler regulator. It should be worth it I think….
Get them from here – http://www.dimensionengineering.com/DE-SW050.htm
Max 12.05 on 28. 7. 2009 Permalink
Use an LM2576 – 5.0V version , up to 77 % efficiency which is good if you compare it with the 7805 .
And it is quite cheap ( 2 dollar ) but you need some other parts ( inductor and diode and some capacitors )
Or you can use these http://www.murata-ps.com/releases/cdped259_78sr-2a.html (up to 96 % for 5 V version !) but a lot more expensive , but you don’t need any other part ( complete pin swappable with the 7805)
Jaromír Průša 18.41 on 28. 7. 2009 Permalink
Bilignual web? uau, Looking forward to see growing
Would You like to exchange the links?
bodhi 14.31 on 29. 7. 2009 Permalink
Great idea. Just curious, do you know how much current the 128 draws? I’ve been thinking of hacking a usb or firewire power supply together…
pinchies 15.45 on 29. 7. 2009 Permalink
Could you use a simple voltage divider circuit to split the voltage into 10V & 2V, then use another voltage divider to split that into 2 5V rails, then use those 5V rails in parallel? I haven’t done electronics for ages.
iPhone 3Gs CZ 18.14 on 29. 7. 2009 Permalink
ahoj, tvůj odkaz na RC auto je nejspíš blbě
EDIT: Díky, byl
pacman 7.26 on 30. 7. 2009 Permalink
Nice project. My question: which theme is it that provides your lock screen wallpaper?
prusajr 7.34 on 30. 7. 2009 Permalink
@pacman Thanks. http://www.usingmac.com/2009/7/1/beautiful-artistic-wallpapers and find Bokeh. I’m using it even on my MacBook Pro
Daily Phones 8.40 on 5. 8. 2009 Permalink
nice project mate ! BTW. great post and great blog! We also invite you to me on the blog
MSI Wind úprava baterky – nabíjí ostatní USB zařízení | NetbookPortál.cz 19.01 on 20. 8. 2009 Permalink
[...] tohle tu ještě nebylo. Kutil vlastník - Prusadjs.cz modifikoval baterii z MSI Windu že teď může být použita k nabíjení jiného USB zařízení, [...]
melatoninEEE 4.35 on 28. 9. 2009 Permalink
MSI Wind is basically good for net surfing and some light applications. for heavy gaming and multi-tasking apps, i would still use those heavy, bulky laptops.
Jean 5.20 on 10. 10. 2009 Permalink
MSI Wind is very very convenient to take wherever i go. it has basic features only but for general internet browsing this is good enough.
Even Larsen 3.15 on 14. 12. 2009 Permalink
You don’t need the voltage regulator, bro. Iphone and iPods are certified to charge for up to 30 volts, so an added component is just wasted money and a drain on the battery. Car chargers for example, or the iPhone included wall charger have an output of 12 volts. I’m doing the same on my Acer Timeline battery, just ordered the USB connectors.
Ksbnok 21.06 on 20. 2. 2010 Permalink
Hi friend I tried the process it took my whole day but could not succeed.. instead of using ur circuit I used a CAR USB CHARGER specifications:
INPUT: 12V-24V
OUTPUT: 5V
Max Current: 1000mA
plugged + & – from ma laptop battery source to it though it was successfully charging my NOKIA phones but not ma iPhone..
I would be grateful to u if u could shadow some of ur knowledge on dis issue
Thanxs! in advance
Ksbnok 21.10 on 20. 2. 2010 Permalink
And for ur information…I must tell u that I also Cross checked the output that the USB CAR CHARGER was producing and it was found to be 5.82 V (more than what was required for an iPhone 5V)
Ksbnok 21.42 on 20. 2. 2010 Permalink
I got ma answer here thanx newayz
http://wiki.siftah.com/IPhone_3G_3GS_USB_Cigarette_Lighter_Socket_Charger
awesome post inspired me to do this stuff…. cheers
Ksbnok 19.00 on 21. 2. 2010 Permalink
sorry even the above sol dint help me
am stuck now…