We'll look for you in next year's Darwin Awards. Don't disappoint us!

-- Larry

That at least supports the notion that the charge controller is in the phone.

If you mean faster than a one-hour rate, it depends.  Commercial Li-Ion charger
designs I have done were based on a maximum of about 0.5-0.7 C.  The ability of
the cells to be charged at higher rates is a manufacturing thing.  What needs to
be considered is that the charging takes place in at least two phases - the
first is current-limited (CL) while the second is constant voltage (CV).  During
the CL phase, the cell voltage rises while the current is held constant.  When
the voltage limit is reached (4v2 typical), the charger limits to that voltage
and the current tapers off.

In our cyclic testing at 0.55C:
.  59% of charge was restored during the CC phase (54 mins)
.  96% was restored by the end of the CV phase (a further 137 mins)
.  the remaining 4% was restored during the top-off phase which lasted a further
63 minutes.

(the above are averages over repeated cycles, but the figures never varied more
than 1 or 2% from these)

The things to note from these numbers are:
.  *doubling* the charge current in the CC phase will cut a whopping 27 minutes
or thereabouts off the total time of about four hours - hardly worth the
excitement.
.  you can't  "force" charging at a higher rate under CV condition without
exceeding the voltage limit - an unwise path - as the rate at which charge is
absorbed by the cell  is determined by the cell.

What can/does happen in consumer appliances - in pursuit of faster recharge - is
that the voltage setting is tweaked to say 4v25, which allows a slightly higher
% charge takeup under CL conditions, and also the CL value can be taken as high
as the manufacturer is prepared to wear.  Both of these measures will provide
faster delivery of the bulk of the usable capacity in reduced time, but the
downsides are there:

.  the CV charge phase (to the extent they bother with it) is still long and
slow; avoiding it means the cell is only using ~60% of it's capacity.
.  cell life will be reduced as a result of the higher charging voltage, and the
increased number of recharge cycles if the CV phase is abbreviated or omitted.

Charging algorithyms are different for different battery
chemistries.....using the wrong charger could lead to failure, fire,
explosion, thermal run away........

Don't do it!

I would like to plug a non original charger to a phone with li-ion
3.6v,550ma batt;
I have 1. 5v,400ma and a 2. 5.6v,700ma
should I use 1. or 2., &I suppose charging electronics is integrated in

batt/phone?

however
the one google suggests for
( T28, T28 world, T28z.
T29.
T39d.
T60, T60d, T60lx.
T61lx, T61d, T61z.
T62u.
T68, T68i.
R320)
is
DC 4.5V-9.5V, Max 800mA
I do not think though  the li-ion are charged with above their rated
current?

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