Mike is talking about equalization, Larry, not desulfating - they are
two entirely different things. And batteries that use a desulfator
still need to be equalized.
There is no need to disconnect electronics or 12 volt equipment during
equalization or desulfation. Unless it is a garage based manufacturer
all 12 volt equipment is designed to withstand those voltages. We
design our 12 volt equipment to withstand up to about 28 volts
continuously and voltage spikes up to 1000 volts or more.
For those that are interested, the following is the "TMI" education on
EQUALIZATION AND DESULFATION.
EQUALIZATION:
A multi cell battery in steady use goes through charge and discharge
cycles. Charging and discharging is the process of putting CURRENT
(amps) into the battery and taking CURRENT out of the battery. The
amount of charge transfered in each case is measured in amps X hours or
amp-hours.
You will notice the word "voltage" did not occur in the first
paragraph. Voltage is used to push current into a battery or draw
current out of a battery. Each cell has its own voltage that is added
up in 6 cells (for a 12 volt battery) to give the battery voltage. All
the cells contribute equally to the current flowing out - they have to
because they are in series and the identical current has to flow in all
of them and they share equally in the current coming in - again they
have no choice independent of the individual cell voltages.
A battery with cells in series is like a chain and it is as strong as
the weakest link. The whole battery is considered discharged when the
weakest cell is discharged. If all the cells have identical
characteristics then they should all reach the discharged state about
the same time.
During charging the charger can't monitor and charge the individual
cells. They all get charged equally and the charger monitors the total
voltage to determine if they are fully charged.
But unfortunately they can't make batteries with "identical" cells -
there is always one that is weaker and will be discharged (or charged)
before the others. This means the unused capacity of all the other
cells is wasted and the battery capacity is diminished to the weakest
link. In fact that weak link will cause charging to stop before all
the tougher cells are fully charged and their capacity is also reduced.
So EQUALIZATION is the process of forcing excess current into a battery
that looks like it is already fully charged. This current will
OVERCHARGE the weaker cell(s) causing them to bubble but that extra
current will finish charging all the other cells that have been
starved. When all 6 cells are gassing then no more equalization can
occur and all cells are fully charged. An equalization charger can't
check if they are all gassing so it usually just overcharges for a
fixed time and assumes they have all "EQUALIZED" to full charge.
In this process, stirring up the electrolyte with the bubbles helps to
destratify any layer concentrations and move any debris (sulfate) from
between the plates.
DESULFATION:-
Sulfation in batteries is usually a symptom of DISUSE. In a battery in
regular use with significant charge and discharge cycles sulfation is
rarely a problem. I'm not knowledgeable enough of the chemical process
of sulfation but sufficient to say you can think of it as crystals
forming on the plates that reduces the area available for supplying
current.
In particular I've found that batteries in long term float conditions
such as at a dock with a charger maintaining float voltage, the tiny
charge and discharge cycles can cause serious reduction in life. I
don't know if that reduction is due to sulfation or just over use of
just the surface of the plates making them spongy but read the article
at
http://www.yandina.com/hints.htm#BatterySaver for information on how
to save your expensive battery bank from "short cycle" damage.
When desulfators came out I read the patent claim(s). It read like
science fiction and I was very dubious of their claims. The patent
indicates that the sulfate crystals have a uniform size and if you
apply a high frequency energy pulse to them and hit their resonant
frequency (about 3+ MHz from memory) you can break them up just like
the wine glass in the Memorex commercial from years ago. However
despite my skeptical impression it is hard to deny the wealth of
accolades from those that have used them.
So EQUALIZATION and DESULFATION are entirely different processes.
Regards,
Ann-Marie Foster,