Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
werto165

Upgraded Laptop Battery

Recommended Posts

Posted · Original PosterOP

I know that quite a lot of laptop batteries are based off 18650 cells do you think it would be possible to buy a new laptop battery and swap the old cells for newer larger capacity cells? I've been looking and the IC for the battery management system (charge controller?) anyway reprogramming it needs kit that costs about £100 whereas a new battery is only about £20 so I thought that would be a better route. Would it be possible to place more cells in parallel to get greater capacity and perhaps 3D print a new enclosure for the improved battery? I know that spot welding is probably required but my university has that capability so I would be fine in that regard 

 

 

https://www.ebay.co.uk/itm/18650-3-7V-4000mAh-BRC-Rechargeable-Li-ion-Battery-Lithium-Cells-UK-Seller/263876035192 18650 cells 

https://www.amazon.co.uk/Replacement-Pavilion-800049-001-800010-421-HSTNN-DB6T/dp/B07DQKXD5G/ref=sr_1_7?crid=1MIWEEQ1DRLVY&keywords=hp+pavilion+battery&qid=1562852302&s=computers&sprefix=hp+pavilion+b%2Ccomputers%2C157&sr=1-7 battery I'm thinking of taking apart


CPU: Intel 3570 GPUs: Nvidia GTX 660Ti Case: Fractal design Define R4  Storage: 1TB WD Caviar Black & 240GB Hyper X 3k SSD Sound: Custom One Pros Keyboard: Ducky Shine 4 Mouse: Logitech G500

 

Link to post
Share on other sites

Yes, its doable and lots of people have videos on YouTube describing the process. That being said, I generally advise NOT to mess with LiPo's if you don't explicitly know what you're doing.

Link to post
Share on other sites

Those batteries are FAKE.

There's no battery in the 18650 package capable of 4000mAh - it's simply not possible with today's technology to achieve that number.

The highest end batteries in the 18650 size reach around 3200-3500mAh but they're very expensive.

The batteries that are mass produced, in volume, are typically in the 2500-2800mAh range.

Here's examples:

 

Cheap Chinese batteries imported by Sparkfun : 2600mAh : https://www.digikey.com/product-detail/en/sparkfun-electronics/PRT-12895/1568-1488-ND/5271298

 

11 uk pounds each / 50pcs Brand name (LG INR B4 2600 mAh) : https://uk.farnell.com/ansmann/1307-0000/li-ion-battery-3-6v-2600mah/dp/2723326

14 uk pounds each / 50pcs Brand name (LG INR MJ1 3500mAh) : https://uk.farnell.com/ansmann/1307-0001/battery-non-rechargeable-3-6v/dp/2889326

^ they can be found cheaper, this particular store is just more expensive (they factor in the shipping costs in the price)

 

The battery on Amazon is basically just 4 batteries in series : 3.7..4.2v x 4 = 14.8+ ... you can see in the pictures they're rated for  2200mAh so most likely they use 2300-2500mAh batteries inside and they're a bit conservative on the total rating.

 

You can increase the capacity of such batteries by adding batteries in parallel :

 

image.png.2da808a460082580f5ab41203faa4142.png

but you must be careful not to mix old batteries with new, because they'll charge at different rate and their maximum voltage may also be slightly different.

Also, the batteries should have the same capacity, basically best to have all same brand, same series, same max capacity to get same charge rate, same discharge rate and so on...

 

The way I would mod a battery would be by carefully soldering a couple of wires to the circuit board and feed that with a voltage close to battery voltage from an adjustable power supply for example, then remove the old strip of batteries and connect the new strip of batteries (with 2 batteries in parallel instead of just one) - basically at no time the circuit board should be disconnected from power as that could make the chip reset or think the battery pack was damaged.

You'd need a high quality soldering iron that can quickly solder wires without overheating batteries.

Then fully discharge the battery as that would probably make the protection chip "learn" the new peak capacity as the batteries charge up

Link to post
Share on other sites

Hmm it might not be that easy, I tried that once and it pretty much failed. The problem is that the battery has a chip, which counts the charging cycles and capacity of its cells, sometimes this can be resetted, however for many models there is no known way to reset it.

Link to post
Share on other sites

On paper, yeah sure, but it would probably be a pain right in the cunninglinguals to fold up the cells and the tabs like they are from the factory. Definitely only add more cells in parallel though, and remember that you're only allowed up to 100W/hrs per battery operated device. 


I used to have guides here

CPU: 4670k 4.4ghz GPU: GTX 970 G.1 1534mhz

Link to post
Share on other sites

sounds like too much effort to me. 

 

I'd rather just buy two laptop batteries. 

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×