powerbook 1400 Battery

[macintoshman]

Hi,

Do you know if I could put in new cells in this battery? New ones are to expensive! :I

Ant I am worried if I do, it will explode like a dell! Please help!

 

[Quadraman]

The cells in any laptop battery can be replaced, but there is electronics inside and you need to be able to solder. The cases are usually sonically welded, too, so once you get it open you'll be on your own to devise a way to get it to stay together again. The cells that OEM's use in their batteries are usually the cheapest ones available. If you spend a little more for high capacity cells, you'll get a lot longer life out of your battery packs.

 

[wally]

...I am worried if I do, it will explode like a dell!...

Leave the protective thermal sensors and thermal breakers in the circuit when you recell the battery, and do not tape over the existing vent holes/slots that are there to let any vented gas dissipate before it can build up. NiMH cells are not known to explode or burn as compared some lithium chemistry batteries. But they will overheat and vent if overcharged, and the power manager in the 1400, if working, is designed to prevent this.

 

[tomlee59]

Get replacement cells with tabs already welded to them. And when soldering these together, don't dally -- heat is the enemy of batteries. You can damage the cells very quickly and permanently with excessive soldering heat. Just keep track of polarities, plan carefully ahead, and you should be ok.

 

[MacMan]

To get the battery casing open you will need to cut round the join with a sharp knife. Sometimes, if you're lucky, it will pop open just by prizing with a screwdriver but more often than not you need to cut the plastic.

Once the new cells are in, the battery can be glued or taped back together. If using tape, beware of vent holes as mentioned above.

 

[wally]

... Sometimes, if you're lucky, it will pop open just by prizing with a screwdriver...

And I second this pleasant thought by MacMan. Those two little tab things at the top front lip are just the place to start prying, unlatching the cover lip then working towards the left and right sides. I got lucky and my case split open along the seam line quite nicely. There is some double sided adhesive stuck lengthwise to the underside of the top cover that adheres to the two innermost rows of batteries, this is just overcome by prying with a putty knife as the batteries topside are cardboard sleeve insulated and all the electronics is underneath the batteries bottom side. You can go in 2 inches in the middle of the topside, it's all insulated. No putty knife prying or deep knife cutting at either extreme end: this is where the bare solder tabs are exposed! If you cut, limit penetration to .080 inches and break the rest free with prying.

 

[Bunsen]

If you fancy it, there's a link in my blog (see below) about building a small spot welder so you can do the battery tabs right. Much better for the components than soldering, and once you've built the (not very expensive) welding rig, probably easier to do.

 

[macintoshman]

Thanks for the help!