Removing the BIOS battery won’t clear the password on any computer built since the early 2000’s at least since all the BIOS settings are held in flash memory (similar to a USB memory stick) rather than in battery-backed CMOS memory. The battery only powers the real time clock, which will probably revert to Jan 1st in the year of manufacture.
You will have to hunt around, but it’s likely there are 2 distinctive solder pads on the motherboard, maybe triangular and/or with some distinctive marking against them and hopefully visible when you remove a service cover from the base of the laptop. You have to short these together whilst pressing the power-on button, maybe for a minimum length of time, or some such protocol.
But it can be tricky, not only to get the sequence right but also to hold the pads shorted whilst pressing the power button. It’s much easier if you solder a pair of flying leads with a push-button switch on the end to the pads.