On Mon, 26 Oct 2020 17:14:14 +0000, John Rumm
wrote:

On 24/10/2020 20:49, T i m wrote:
On Fri, 23 Oct 2020 16:14:41 +0100, John Rumm
wrote:

I've just been given a Makita DTW190 impact wrench and mating BL1830B
battery but no charger. I was given it without charger because the
person believes I have a compatible charger (and other battery) but I
can't find it atm.

So, in the meantime I charged the battery using my GP charger and it
now show 4 out of 4 charge LEDs ... and I'm going to 3D print a
charging clip off Thingiverse to make that process more
straightforward.

The multipin connector on the battery looks like it could be a balance
connector of some sort but I couldn't see any voltages on it from a
quick look with the DMM so have to assume the BMS in there looks after
the cell voltage balance itself (not the charger)?

Is there a basic / slow charger out there that's cheap, in case I
can't find the other one (and assuming it's compatible if I do)?

I don't think I have seen a slow charger for the LXT batts.

Shame ... if you don't need it in a hurry (or have enough batteries to
carry you over) then I feel slow charging is the better bet.

Note that these things have temperature monitoring and fan assisted
active cooling as well.

Yeah, I think that's what the smaller connector on the battery pack is
for, to pick up the thermistor in the battery.

The idea being you can take a hot battery
straight off a tool and put it on charge immediately. Whereas with older
charging systems this would be a guaranteed way to knacker a battery in
a fairly short time, its now the recommended thing to do with a hot
battery.

Yup, like we used to do with RC car batteries years ago. ;-)

The charger will sense when its too hot to charge, and blow
cooling air through it until its down to a safe temperature before it
charges it (and cools while charging and for a time after).

Cool. ;-)

The basic charger is not actually that expensive all things considered:

https://www.lawson-his.co.uk/makita-...18v-li-p148254

Hmm, given I was given the impact wrench and battery, that makes it
quite expensive, given how often I might use such a tool.

Same with impact drivers (after the last mention of them here),
a(nother) mate gave me his spare one when he went over to a single
brand for things. I tried to use it on some 'tough' screws and all it
did was break the bit (it was probably a cheap / non impact driver bit
etc).

I note there are a few clone Makita chargers for about 20 quid but
I'll wait till I come across the other battery and charger I have
somewhere before buying anything.

I've printed a slide connector clip that was designed to be a diy USB
outlet. I'm going to fit a switch allowing it to be a USB charger and
when flicking the switch, it turn off the USB and connects the battery
to an input for charging on my smart charger (for now anyway).

Cheers, T i m