Laptop with lost battery : what voltage ?

[Mika-L]

Dear all,
I try to use an old laptop after beeing stored many years. I replace hard drive by SSD, etc, it works great enougth for what I want to do. Unfortunately : the battery was not present, and when I try to buy a new one there are two possible voltages : 11.1 V and 14.8 V. The manufacturer (ACER) has no information about the wanted voltage for this model. So is there anything I can do to "guess" it ? I tried to inspect the pins with a DC voltage meter (for example I hoped the PC tried to load the battery) but I did not find any voltage in the order of magnitude by more than 10 V.

Any idea ?

Regards,
Mike

 

[Harald Kapp]

The manufacturer (ACER) has no information about the wanted voltage for this model.

If not the manufacturer, who else?
What model is the laptop?
Measuring on the input pins is useless, you will not find the required voltage to be supplied there by the battery. The laptop should detect that no batters is present and consequently should not try to charge.

 

[Mika-L]

The manufacturer does not know that's why I ask whether there is or not a kind of reverse engineering with electronics ... Perhaps a "well-known protocol" somewere or anything like that.
Perhaps is it possible to simulate the presence of a battery to load for example, but I guess there is something like SPI protocol to communicate with the laptop ?
The model is ACER extensa 5220-210G12Mi
Thanks,
Mike

 

[Bluejets]

https://www.ebay.com.au/sch/i.html?...w=battery+ACER+extensa+5220-210G12Mi&_sacat=0