Getting The Maximum Use Out Of Your Laptop Battery At CVHS

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Getting The Maximum Use Out Of Your Laptop
Battery At CVHS
How I Did the Experiment Representative
Lithium Ion battery samples were secured from the
CVHS Computer Cart. The samples were then totally
drained prior to recharging. The first recharges
were done for almost a day (22 hours). Then the
battery, presumably at full charge, was fully
discharged in a constant process of computer use
playing the same song again and again at the same
volume until total discharge was achieved. The
time was then recorded and paired with the
initial charging time. The process was
repeated with shorter charging times. Each time a
charging time was recorded, the same discharge
process was used to totally discharge the
battery. Thus the average charging and
discharging times were established for each
charging time interval. The results were
translated into graphic representations which
will follow. They yielded some unusual results
which I would not have predicted.
By Rachel Lee
Why the Physics Experiment? Reducing
unnecessary use and establishing an optimal
charging time are very useful pieces of
information for industrial and individual
computer users of the magnitude of Crescent
Valley High School. Overcharging batteries leads
to thousands of hours of wasted electricity in
times of global warming and tight school budgets.
If optimal charging times can be established
based on real school data, electricity can be
saved and that money used in other parts of the
educational process. In addition, this
electricity would not have to be produced which
could decrease global warming from the
electricity production process and the heat
produced from the battery chargers being plugged
in and not charging or inefficiently charging.
Establishing optimal charging times may lead to
longer battery life and thus reduce toxic waste
disposal at landfill sites.
What Conclusions Can be Drawn? Assuming my
batteries were representative Lithium Ion Battery
samples, and my measurements were accurate, as I
believe they were, no battery should be left on a
charger for more than an hour at a time. If more
time is spent recharging, this is a waste of
electricity and an unnecessary addition to global
warming. In addition, since the chargers
produce heat themselves just being plugged in and
not charging, they should be unplugged when not
in use.
What I Learned From my literature search I
learned that Lithium Ion Batteries were not
supposed to be subject to battery memory so they
did not have to be totally discharged to be
placed back on the charger. This freed the
computer user from having to totally discharge
the battery or have it die at an undesirable
time prior to recharging. This also freed the
batteries to be put on the chargers at any time
when they were not being used or from being left
on the chargers as a matter of course. The
results of my physics experiment showed that a
much shorter charging time is recommended to
obtain a complete recharge. It might be
summarized as any time over an hour for these
batteries is overkill for the efficiency of
recharge and is a waste of time and electricity
for the school. Less is truly more. 22 hours on
the charger (my first recharge time) was overkill
in terms of the electrical output produced.
In general by recharging the Lithium Ion
Batteries as presecribed in this experiment, the
school should reap significant cost savings over
time which can be devoted to other facets of our
education. The environment too should reap
benefits from reduction of unnecessary
contributions to global warming. This is truly a
win-win situation. The school wins in cost
savings. The environment wins in decreased
unnecessary global warming.