Battery pack refurbishing with new Li-Ion cells? Opening the battery?
Battery packs, original or substitute, are mighty expensive, and there is no guarantee how long the substitutes might last, since there is no way that one can figure out the manufacturer and quality of the cells inside the sealed battery pack when buying it. So it would certainly be worthwhile to refurbish the original Dell battery packs if at all possible.
Is there anyone who has been able to open a Dell Inspiron 6000 6-cell and/or 9-cell battery pack and re-close or seal it adequately, and can give or has given precise illustrated or video instructions on how to do so on YouTube or elsewhere? Replacing the depleted cells with fresh ones like Sanyo (best, with highest mAh) inside the battery pack would be a relatively easy project provided one is careful with the procedure and polarity.
But what is worrisome is that despite doing so, I have been given to understand that there is a special, sneaky electronic circuit in the battery pack which is intentionally programmed by Dell to block the PC's access to the battery cells(even if the cells are OK), after a specific number of hours of use or a specific number of recharge cycles, so even after changing the cells inside, the battery pack will remain dead, i.e. inaccessible...
I can't answer all of your questions - but let's start with a few infos.
the "round" formfactor of the battery tells me that there are "18650" cells inside the battery - you can use something like the "SANYO 18650 3.6V 2.6Ah/2600mAh Cell" for that, but they are expensive.
you could build a 5.2Ah (6 cell) or 7.8Ah (9 cell) battery with them.
the "conspiracy theory" about the charging counter came up on many devices, mostly MacBooks have those funny problems ;-)
in fact, those dead batteries are not ok, i disassembled a few MacBook batteries and tested the li-po cells - there was always one cell that had a problem while the others were fine!
since those batteries are only using simple charging electronics - they orienting the whole wharging process on the weakest link. they don't have real balancer (as used in the R/C scene) - so if one cell is bad - the whole pack is "dead" - replacing the bad cell with a known good one will revive those batteries (thats why many "freaks" are buying dead MacBook batteries on ebay - buy 6 dead ones for 10 bucks or less and sell 5 working ones for togehter ~250$)
i think you won't need the exact video for your battery - here's one that shows the changing process in common: CLICK here
It doesn't appear that the specific 'ask' has been answered, so for completeness...
Many products such as battery packs with 'no serviceable parts inside' (as opposed to no user serviceable parts) are not even glued together, they use a sonic heat process to melt the plastic at the edges in a permanent 'weld' process. They do this primarily for speed and cost, but I think they also appreciate the side benefit that assemblies are impossible to disassemble without leaving visible marks. Visible marks indemnify the manufacturer in case of disaster or injury during use following modification.
How to disassemble? Depending on the product and your skill, use your own imagination. I would probably use a dremel tool with a thin blade and attempt to follow plastic seams. Obviously care is needed to avoid cutting through the battery cells' metal container. It would be best to cut at an angle or perhaps halfway across a seam at one angle and a different angle for the other half so that the angles help with realignment upon reassembly. For reassembly, use glue and fill the saw gap. Hot glue would possible work well. File or sand any aberrations.
Another respondent described (did not necessarily recommend) the practice of replacing the single bad cell in a series-pack. So, it should be noted that li-on batteries have limits on the number of charge-discharge cycles that they are capable of; they do wear out. If not replacing all cells (regardless of whether they presently work) one would be limiting the life of the repair to the remaining life of the not-new cells. A person's time and effort may be worth more than the cost of replacing all batteries in one shot.
While you're at it, build a back-up pack...