9 May
2013
9 May
'13
1:13 p.m.
On 2013 May 9, at 12:10 PM, David Riley wrote:
On May 9, 2013, at 2:03 PM, ard at p850ug1.demon.co.uk
(Tony Duell)
wrote:
Modern NiMH and Li-ion batteries are great for things like cameras
and bike lights, however I stay away from batteries for power tools,
the really annoying problem being the manufacturers (or some) have
taken the pay-through-the-nose captive-market approach for replacements.
I tried to fix a couple of Makita battery packs for a friend by
replacing some cells, but after the battery circuit was opened and
the internal controller powered down it bricked itself. There is what
appears to be a communications connector in the pack, presumably
there is a way of telling the controller to recognise the batteries,
if one knew what it was.
It occurred to me before doing the work it could do this and if I
were being really cynical-paranoid-careful I should temporarily wire
a parallel supply with isolation diode before opening the battery
circuit, but didn't bother. C'est la vie.
Friend only got two/three years out of the drill and two battery packs.
I must admit I've never liked recheargeable
battereis. They als
seem to
have a ridiculously high self-discharge rate, so unless you use the
device all the time (and thus keep it charged) , you will find it
flat when
you want to use it. I would always pick the direct-mains powered
tool.
For regular household use, the newer low-self-discharge NiMH batteries
have worked well for us. We put the AAs in C size adaptors for use in
a baby swing, and it ran the swing for a good week on a charge (not
100% duty cycle, of course, but not bad for AAs). We've been using
them for about two years now and none of them seem to be showing signs
of decreased charge life, either. I'm not sure I trust Sanyo's claim
that you can stick them in a drawer for a year and still be at 75%
capacity, but they're not as freakishly bad as the NiCd batteries of
the early '90s (which was previously my last exposure to normal
household rechargeables).