Nope have no idea how to recalibrate a laptop battery. Do know the voltages you measure with battery out of the laptop are not same as under load.
Most of those older batts are made of multi lithium cells and one can go bad when rest are OK which then causes a V.drop under load even when fully charged, if the battery is more than 10 years old and having issues and you really like that lappy then order a new battery. Just my opinion....

I've opened the battery up and I've been measuring the cells directly. it's rated for 14.8v and it has 8 cells in 4 pairs. Each pair is measuring 3.7v. Using a bunch of computer fans I was able to put it under a 1.5A load and the voltage didn't drop below 14.5v until I had been running them for quite some time. So the cells seemed ok, and it would charge and power the computer, but it would keep flashing the error lights. I desoldered the controller board in the battery in hopes that it might force a recalibration routine or something by losing all power, but I think I killed that board as it no longer will charge or power the computer (still good voltages though).

I'd buy a new battery, but all the reasonably priced ones are on eBay and are US shipping only. I'm in Canada so the ones available to me range from $50-150 with shipping. It's a bit steep for me to pay for a 20 year old laptop. Especially if I had a US address less than an hour away from me it would be 1/3rd-1/2 the price.

After getting those results of battery test, I would suspect the charge controller board in the unit

Have you already tried the recommended recalibration routine? - https://www.dell.com/support/kbdoc/en-uk/0002 … n-a-dell-laptop