Laptops, batteries and AC adapters
Friends who own laptops told me their ideas. I list them here together
with mines.
Why don't laptops contain their AC/DC transformers? The volume of those
AC adapters is quite little compared to the volume of the laptop or
notebook. Incorporate them in the portable computer would not make a
lot of difference in the device volume and weight. Also, while lots of
adapters heat significantly, the best ones don't heat much compared to
most laptops' processors. A
standalone AC adapter really is a pain. It has to be dealt with
constantly and is much more cumbersome than a simply AC wire.
Lots of laptops have a big battery with at least one side apparent on
the laptop's side. Lots of people don't use their battery and would be
delighted to have a sort of fake replacement battery that would be an
AC adapter. That fake battery can possibly contain just a little
high-current Ni-Cd battery with an autonomy of a few minutes.
Rechargeable batteries wear out each time they are used and recharged.
Manufacturers claim such a power cell loses most of its storage
capacity
after about 1,000 cycles. Actual measurements are below 500 cycles.
This is due to the formation of parasite
crystals inside the cell. The chemicals involved in the storage of the
electric power are being trapped in those crystals. Now, methods exist
to dissolve those crystals without opening the battery. A high
frequency signal has to be applied while the battery is being charged.
Why do laptops and cell phones not contain such a battery regeneration
device? This just implies a dedicated rudimentary microcontroller and a
few more transistors. Note it can be this manipulation is somehow
dangerous. Maybe it needs safety devices like temperature sensors or
maybe it should be completely avoided or entrusted to specialized
technicians. I don't know.
It seems current Li-ON batteries have none of the memory problems own
to the Ni-Cd batteries from long ago. Ni-MH batteries are claimed to
have no memory effect but I experienced they have. Anyway, why weren't
those batteries split in two, three or more sub-batteries? Only one
sub-battery would be consumed at a time. It would not be recharged
until it is empty. When the laptop is connected to the AC all empty
batteries are being charged till they are full and become available for
consumption.
Thanks to Pierre Backers, René Gommes and Didier Bizzarri.