[chbot] 18650 battery sources

[Volker Kuhlmann]

On Wed 26 Oct 2016 14:26:05 NZDT +1300, Andrew Errington wrote:

> I haven't used 18650 batteries yet, so I am interested in what people are
> using them for, how they are using them, and why.

Everything that NiMH AA is used for, and then some. The main
differences:

Basically zero self-discharge.
Very high energy-density.
More practical output voltage.
Can be paralleled without issues, for discharging. For charging, within
reason.
Plonk a protected 18650 into your (attention: must physically fit, can
be 70mm long) into your flash/head/XYZ-light, and it's hands-off zero
worries. Eventually the light goes out. With NiMH, the light goes out
too, on top of that, your battery is f-f-f-...inished.
Good-quality 18650 are not dangerous, if handled within specs. At a
meeting long ago someone said at Taits experiments to smash/drill/etc
them did not produce excitement. The Pyrotechnics come from LiPoly etc.,
which have an even higher energy density (let's call it the
SamsungNote7-effect...).

The cost:

Must have good-quality charger. Charge limits are critical to 10mV or
less.
Cheap Chinese Sh.tFire may detonate during charging. The Internet is
full of examples, including pictures. Charge in bomb-proof
well-ventilated space away from combustible material bla bla bla.
Unprotected batteries are seriously damaged or destroyed from being
under-discharged once. You get more life by operating within 3.0-4.1V
only, at the cost of what, 5%?, capacity loss.
Different handling. Store 1/2-2/3 charged, not fully.

Volker

-- 
Volker Kuhlmann
http://volker.top.geek.nz/	Please do not CC list postings to me.