Help/advice please re replacing a power tool NiCd battery pack with a DC transformer

Hi,
I am new to this forum and would appreciate your help and advice. Please tell me if I am in the wrong forum and/or the topic is not relevant.
In this case, I would also appreciate if you point me to the right direction/forum.
My question is that I am not going to replace the battery packs of this power tool with very expensive replacements and/or batteries.
So, I would like to get a transformer which could supply the required power and the torque
The power tool in question is a 14.4 V/ 2.0Ah impact driver.
I am afraid I have forgotten how to calculate the correct rating of the transformer [I could do it about 50 years ago...]
As I am in the UK, the AC voltage is 240. So, what rating of a transformer should I think about/purchase/build?
Thanks.

The battery may have two amp hour capacity - but the tool load current could be anything, lower or (more probably) higher than 2A.

How long does (or did) it work continuously for, at full load, on a single charge? That should give an approximation of the load current to base things on..


As another approach - 14.4V implies a 12 cell NiCd battery pack.
That has a voltage range almost 18V immediately off charge down to 12V dead flat.

It would cost roughly £14 for four, good quality 2.5AH 18650 lithium cells - which would likely work OK & may even fit in holders in the original casing? They give a voltage range well within the original NiCD range, so should be totally compatible.
eg.
**broken link removed**

You would need either a separate cell charger and remove them from the holder, or build them in (using cells with solder tags), with a four cell protection & balance board, then use a suitable external four cell charger.

Example BMS with balance, rated for power tools:
**broken link removed**

If you use the tool by your automobile, evaluate hooking it to its car battery with alligator cables to see if it performs to your satisfaction.
For true portable, check if a bunch of 18650 cells can be made into a pack, in the original housing/contacts, but you will need to work on the charging scheme.
A 240VAC to 14V/2A+ adapter from mains may be dissapointing. Try one if in your means.
If you are willing to drag an adapter to 240VAC everywhere you use the tool; you may be willing to trade the drag with a motorcycle battery; about the same bulk.
Original battery packs are a shame of price gouging and deserve out of the box views.

A car battery charger would also probably work, you just need a reliable means to connect to it.