How to: Prepare the IBM Thinkpad 710T battery for display
Here I will show how to turn a leaky laptop battery into a safe display battery. Display means it will look like new, it will attach to the laptop and look totally functional, but will not have the nasty leaky cells inside. These leaky cells will kill your prized electronics slowly but surely, so best thing to do is get rid of them.
On the theme of leaky batteries - I collect film cameras, one of my favorite are the Canon film cameras, which are the first camera to feature a microprocessor for aperture and speed. You know if you have a film camera with battery in its manual it is specifically said to remove the battery for prolonged stay as it will eventually leak. It will destroy all the connectors around it and will promote corrosion on soldered components.
Also the Ni-Cd or nickel–cadmium battery in your Thinkpad is bad for the environment, probably for you too, so why not dispose of it properly and save your laptop from deterioration.
To recycle visually your Thinkpad 710T batteries we need these supplies, which are easy to find on the net or at the hardware store: 1 spray can of "Flat Black", one of "Matte Clear Coat", masking tape of your choice, Exacto knife with new blades or a hobby knife, epoxy or even better acrylic glue. The acrylic glue is suggested as it comes in two bottles and is mixed 50/50 before application, or part A can be applied to one halve of the battery box and part B can be applied to the other. What this does is it gives you time to carefully apply the two components without the glue setting to the individual halves and then mate them together. Once they are mated the chemistry in the glue will react and solidify the acrylic in to a solid weld.
The IBM Thinkpad 710T has a battery shell that is ultra-sonic welded. This process makes the two halves of the battery casing virtually inseparable, which is a problem for the display idea, as it makes the separation and removal of the batteries tricky. This is where the Exacto or hobby knife comes in. !Warning! If you don't have experience with properly handling exacto knife, do not attempt this, you will get seriously hurt, there will be blood too! Exacto is a great tool, but more often its use leads to bleeding and deep cuts. DO not work with the exacto towards you, make sure your motion leads away from your body and your fingers. DO not apply any pressure on the knife while you are working. The Exacto is very sharp, the plastic is very soft, just repeat line after line your cut path until the halves are separated.
Alternatively you can use a Dremel rotary tool with cutting disk to separate the halves. This is the safer method, however the cut/separation line will not be as precise and clean as when your are using the Exacto, and it is very possible that you will cut into the battery cells, which I don't know if it is good or bad.
I've spent many hours model making and prototyping with the Exacto knife and know how to properly use it to cut plastic, so I will use a (similar in function to the Exacto) hobby knife I have laying around to separate the shell and remove the batteries inside.
The spray paint I need for recreating the rubbery finish on the Thinkpad, which by now has totally decayed, makes black stains everywhere, it is sticky and visually destroys the glorious Thinkpad 710T. I've bought Tamya's model spray paint for plastic models, but from my experience the solvent inside is the same as the one used on auto-paints, so probably a regular car spray paint will work as well.
The masking tape I need to cover the shiny portion of the battery housing, the portion that does not have the rubbery finish and has all the warning and info stickers on it.
Lets get started:
This is what the IBM Thinkpad 710T battery look like. To get the rubbery finish off the battery I used "Mr. Muscle" - the actual kitchen cleaner that is. It contains ammonia in small quantities, but just enough to melt the rubber finish without destroying the ABS/PC plastic (ammonia will kill ABS and PC if in enough concentration). Then rinse with hand soap and warm water few times and let air dry.
You can see the halves of the housing separated at the original mating area. There is a groove there where the halves meet, this is where I repeatedly rolled the knife, until the assembly came loose. You should know it will take time and effort and some sore fingertips. Just score the plastic in one continuous line along this groove, over and over again without using force, eventually the knife will cut the plastic.
The battery housing opened. You can see the rows of batteries
And you can see some leaked cells too.
The batteries have two short circuit breakers "Klixon" like this:
An one breaker I am not sure of.
Batteries out of the protective paper tubes, looks a bit like intestines
And finally the two halves of the assembly empty and ready for gluing back together. Note the metal contacts and their attachment to the plastic. This area will have to be reinforced with some glue as it had to be cut on one side when separating the halves. Just glue the metal plates to the plastic and then reinforce with some glue the base of the plastic legs which hold the metal contacts in place.
Here is the battery already glued and painted. Sorry forgot to take pictures of the gluing and masking process, but it is just a matter of masking the bottom shiny halve and making sure paint can't get to it.
This is one of the side access doors before paint just to give you an idea of the simple paint settings I had.
Here is the same door painted. See how the faux rubberizing came, it is matte and textured, this is what you need to achieve when painting. Note color is not as black on the picture as it actually is, probably aperture and speed of my camera was not set properly.
And the actual "display" battery finished.
You need to mask the originally shiny bottom halve of the battery that has the bar code and labels on it so that when you spray you will only paint the top (originally rubberized halve). See the separation between paint and original finish on this pics. Top is matte and bottom is glossy.
Here is a picture of the supplies I used.
These are basic model paints that you can by anywhere on the net, they are not expensive and work great for plastic. You need to clean the surface of the plastic from any residue or left over rubber coating before paint application. The black matte paint itself (as any other paint) is very thin, only microns so it is not really good for texture and is not strong at all. You need to use the clear coat ,which is very thick to actually preserve the paint and the finish. So first you spray the black paint to get even and uniform coverage (since it is matte it will hide any painting mistakes you make while spraying. Glossy paint will leave your spray path visible together with the over-spray you will certainly make, due to the use of spray can instead of spray gun). After you are happy with the uniformity of your paint you need to create the texture again using the black paint. Here you need to gently push on the spray head in short intervals and further away from the area to be textured as when you were making the base color. You make one pass over the whole area with short bursts of paint and then wait 10-15 min for the texture to set. The texture is created when semi dry paint from your short spray bursts is overlaid on the base paint and let dry. Repeat until satisfied (note: it will not be the finished texture, this will be achieved with the clear coat).
Now repeat the exactly same paint process with the flat clear coat. Remember to cover all edges first and then apply the clear to the main surface area. The flat clear coat will protect the paint from scratches, and will make the paint stronger.
The sand paper is 1500 grid and was used to smooth out the halves separation edges so that when glued they will fit better and keep the original battery dimensions.
So, that is it, you have a "display" battery for your classic laptop. Remember this is for display purposes only, you spent 20 USD to make it look like the original melted and decaying rubber, and not as a replacement of the original. The original rubber coating on the Thinkpad was produced with a very complex and expensive processes, which naturally was on purpose: IBM laptops had a soft non-slip finish that no one will ever want to copy, because it will be too expensive to do so. This is how Thinkpads stayed innovative and exquisite.
Tamya online spray paint catalog