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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default High output alternator on a Bukh DV24

Jeff wrote in
:

Why are you so obsessed about this, Larry? Its gotten to the point
that you're just ranting nonsense!



http://www.batteryuniversity.com/partone-13.htm
Boiling the **** out of it isn't going to give it a saturated charge.
It's voltage comes up because the plate surface becomes coated, but
that's not charging it.....correctly.

http://www.batterystuff.com/tutorial_battery.html


http://www.bigginhill.co.uk/batteries.htm
which says:
"The Bulk Charge

In this first part of the charge the battery is allowed to have a large
draw on the available current. Usually the limit to this current level is
determined by the availability of a suitably sized mains outlet,
especially on large batteries. It is however, worth noting that that the
life of a battery will be greatest if even this first bulk phase of
charging is started off gently and the maximum current is limited. If the
current is too high the result will be excess heating within the battery
which is wasteful and could lead to buckling of the plates and
destruction of the battery. Sizing of the charger to suit the batteries
is important.

Finish charge

Once the bulk phase has been completed, the finish phase commences and
the battery charge is topped off. This phase is very important. If the
battery is not topped up gently it will overflow in the form of waste
heat and violent gassing of the plates which again can lead to the plates
buckling and the battery being destroyed. If the battery is not topped up
fully, it will become sulphated after only a few charges and the result
will be premature failure.

Equalization

In any cyclic application, a series of batteries will always need to be
equalized from time to time in order to ensure that the battery cells
remain at the same voltage throughout the pack.

No two battery cells or batteries are created equal. During both charge
and discharge each and every cell/battery will react in a minutely
different way to its neighbour. This could mean that each battery may be
holding a different quantity of charge. In order to get the most out of
the total battery pack it is necessary to make sure, as far as possible,
that each and every battery is holding a similar amount of charge.

During the charge cycle the voltages of the different batteries will
very. In order to bring them all to the same level it is necessary to
give some a slight overcharge in order to bring the other up to full
charge.

Equalization is done by allowing the voltage to rise while allowing a
small constant current to the batteries. The voltage is allowed to rise
above the normal finish voltage in order to allow the weaker
batteries/cells to draw more current. The stronger batteries will not be
adversely affected providing the current is gently and the period and
frequency of overcharging are not too high and great respectively. The
stronger batteries will absorb the overcharge by giving off heat by
gently boiling and gassing more heavily. Once the weaker batteries have
absorbed the required current, the equalization charge can be halted. The
equalization time should be long enough to bring all the batteries up to
a full state of charge. As the time factor will very the most reliable
way to check the charge states is by a voltmeter on each cell or
individual battery.

Really sophisticated battery charging and monitoring systems do not
require the use of an equalization charge and are able to charge all the
batteries fully including the weaker ones without overcharging the strong
ones.

In these systems, each battery is fitted with an electronic clamp, which
gradually reduces the amount of charge going into the fully charged
batteries as the finish charge progresses. This means that the weaker
batteries receive more current to bring them up to a full state of charge
and the strong batteries are prevented from being overcharged
unnecessarily. The drawback with these sophisticated systems is their
cost. The price of each battery clamp can be in the order of 1/5 the cost
of each battery."



Wishing it will charge in an hour is simply dreaming and really not good
for any lead acid battery, no matter how much it costs.

But, you have it YOUR WAY....(c;

Larry
--
Democracy is when two wolves and a sheep vote on who's for dinner.
Liberty is when the sheep has his own gun.