August 29th 2008.
Lead-acid battery technology hasn't changed that
much in many years, but refinements continue to be
made.
If you're looking at the last few years, the changes
we have seen in battery technology are more about
manufacturers
tweaking their batteries in their processes -
mostly the chemical and manufacturing processes.
In recent times, battery
manufacturers have been investigating different
alloys, like silver, or tin, to strengthen their
batteries' plates or give them
properties that will make them last longer. For
the same reason, the separators between the
positive and negative plates
have been improved.
One technology that some manufacturers are using
is an absorbent glass mat (AGM) in which electrolytes
(sulphuric acid)
are absorbed into a fibreglass mat. AGM batteries
are often used in high performance vehicles, because
the improvement
does come at a cost. AGM batteries can be impacted
even more heavily by temperature than traditional
batteries but that
may actually be an advantage in Canada. These
AGM batteries really like cold weather, but you
have to be careful how fast
you charge them. They are much more sensitive
to being charged properly than the old batteries, but
in a colder environment,
they can take an enormous charge very quickly.
Extremes of heat and cold aren't the only strains
on todays' batteries and electrical systems. The
growing number of accessories
that rely on a reliable and constant electrical
supply is growing by the day. Entertainment systems,
global positioning systems to
name just two, are creating pressure to develop
bigger and better alternators and other improvements
such as brushless,
digitally controlled alternators to better handle
the enormous demands that modern cars place on their
electrical supply.
Some alternators are hooked up to the CPU these
days and although not every car manufacturer has
climbed onto that
bandwagon yet, the trend is obvious.
In Europe, digitally controlled alternators have
been popular for several years. The advantage is
that the "check engine" light
now monitors the alternator and makes our diagnosis
that much easier.
With older cars, one of the problems is the lack
of an automatic battery shut off system. While
a lot of newer cars will have a
20 minute shut down system if there's an excessive
battery drain, once the keys are removed, too many
drivers often leave
on systems that cause an electrical drain down,
such as rear window defrosters and cell phone chargers
that kill batteries
in a hurry.
New devices are often back-installed into older
cars that aren't properly designed to handle the
new electrical system strains.
For this reason. it's very important these days
to test a battery charging system whenever a car
is in for service, perhaps
during regular oil changes, as drains on the battery
happen frequently.
These days, a great many drivers simply don't
drive far enough to meet their batteries charging
needs.
Retirement people who only drive a few kilometres
a week and then only on specific days, are the
problem candidates for
battery failures.
You don't really want to deal with a battery failure
when you're all dressed up and on your way
out to a fancy dress ball
(or something). There's really no reason for a
driver not to know the condition of their battery,
since they should be asking
for this small and quick service job to be done
at least four times a year.
A garage will not generally do it unless asked,
because the resultant small increase in the total
invoice cost can cause
problems with some customers. Trying to predict
the failure of electrical components is similar
to trying to predict the day
on which your TV set is going to fail. It simply
can't be done. But testing from time to time, WILL
detect deteriorating conditions
that will eventually lead to failure.
In the Fall, we do a lot of such testing and the
tow ins in January are almost always clients whose
electrical system had
problems back in October.
I told you so, though, doesn't really cut it with
a client who had to wait several hours for a tow,
even though it is really his or her fault
for not listening.