Battery Charger and Battery Hints-Tips
We were 100 years old in 2007, and have making Schauer Battery chargers since the 1930s.
Battery charger and battery safety information. Battery charger instructions.
Battery charging guidelines. Hints and tips for longer battery life. A place
to get answers to your questions.
Disclaimer :-) We've been asked a lot of questions over the years. I'd
like to post some of the answers on this page. (Red is positive. Charge with
the caps on. Protect your battery from high temperatures, park in the shade.
The negative lead in charger output cables that are bonded together as a wire pair has a rib along its length, small but you can feel it with a finger nail,
etc.) If you have a question, send it by writing to:
You'll see the answer here.
FOR ALL YOU STUDENTS
"Hi, I am student doing one of my major assessments, in the subject chemistry,
on the lead/acid battery. I have been unable to find much information on the
net about my topic and would really appreciate if you could send me any
"I am a grade 11 chemistry student. As a part of the curriculum we are
required to do a project with some relation to the subject of chemistry.
My topic is batteries.
One of the subjects that I am covering is rechargeable batteries. If it
is not too inconvenient, would it be possible for you to send me some details
about how the chemistry of the recharging process works."
"I am an engineering student in the subject of electricity and I have to
define all the battery's parameters (batteries for electrical vehicle). I
would be grateful if you could help me in this project."
There is a battery news group, sci.chem.electrochem.battery. Lots of questions
and answers are posted there. Post your questions there as well.
A superb commercial web site I have found for battery chemistry information
is www.accuoerlikon.com, the home page for Accu Oerlikon, a Swiss battery manufacturer.
From Oregon State University, try Prof. Michael M. Lerner's lecture notes on batteries.
One of our other pages has references.
There you will find a reference to a web site I call the list
of everything. This web site has hundreds of references to the
electro-chemistry literature for the last fifty years. Each of these contains
many other references. What does that tell you? Simply, no one really knows
everything about batteries. There are details to be discovered.
In just the lead acid batteries being sold today there are at least 25
difference types of battery chemistry. And I assure you that the people who
make those batteries are not 100% sure of how to manufacture them nor how
to charge them. Details are being investigated and improvements are being
discovered all the time. Maybe you can discover some.
Don't charge in the rain.
"I was recently charging my battery outdoors when it started to rain.
I became concerned, because I know that water conducts electricity. Is it
very unsafe to connect a charger to a battery in wet conditions? Please don't
tell me to experiment...I'd rather not. :)"
The rule is: Don't charge in the rain. Actually water doesn't conduct
electricity very well. If it did, every time it rained all the power lines
would short out. Salt water is an exception.
It turns out people are better conductors of electricity than water.
So if you reach into or touch water that is covering an electrical appliance,
the electricity finds an easy path to ground through you, shocking.
This is why our battery chargers have a grounding conductor, and
so should your extension cord and outlet. It is why hair dryers now come
with ground fault detectors built in; to turn them off if they fall in a
Remember this, if an electrical appliance falls into water do not
reach in to get it. Unplug it first. Why you ask, because the electricity
will go from the water into your arm and kill you.
So what should you do if during charging it starts to rain? Unplug
your extension cord from the outlet. Then don't use the charger until it's
dried out. By the way, before using an extension cord, check it over for
cracks in the insulation. If there are any, don't use it.
THE CONCRETE FLOOR QUESTION [I love this one.]
"I enjoyed visiting your Web site. At work, several of people on staff
were discussing charging a battery and the effect that placing a fully charged
battery on concrete would cause the battery to lose its charge.
Their statement is that a battery placed directly on concrete will quickly
discharge, while a battery placed on a 2x4 above the concrete will not discharge
There is a newsgroup, sci.chem.electrochem.battery. This question has been
extensively discussed there. I do not have the old posts to pass along. Perhaps
you can find them in news group archives.
My opinion is: The only way to resolve this question among friends, in
order to stay friendly, is to take two matched batteries, place one on concrete
and one on a board. In other words, use the scientific method. Try to get
everyone involved to sign off on the test protocol first to avoid further
infighting. It is my experience that this matter cannot be resolved among
friends by theoretical discussion alone.:-) Let me know what you find out.
Suggestion for further work, is a board necessary? How about plastic film,
wax paper, metal foil, etc. Have fun.
Theory guides, but experiment decides.
"I wish to know if running vehicle in the daytime with headlights on reduces
gas-mileage and the battery life time, and how much."
If the headlights are on, the dashboard lights and the car's rear lights
are on too. Assume the current drain is 20 amperes, more or less depending
on the type of car. That will be about 240 watt-hours for each hour of driving
time. That energy has to come from somewhere. Your gas-mileage will decrease.
How much, I leave as an exercise for you, dear reader, to figure out for your
The effect on battery life should be nil. Two factors most responsible
for decreases in battery life are high temperatures, and frequent deep discharges
of the battery.
"How can I find out who made my battery charger?"
If your charger was listed by a Nationally
Recognized Testing Laboratory, such as Underwriters Laboratories Inc.,
UL, there should be a control number near the listing mark. UL can identify
the manufacturer from the control number.
WHAT BATTERY FOR A SPECIAL PROJECT
"I'm building a robot for a national competition in April. I'm going to
be running 3" motors that run at 2 amps no load and peak out at 95 amps at
stall. I need to be able to run for 5 minutes tops, probably less. There
are no restrictions on battery style, however sealed would be preferred.
What size (amp/hours) do I need to purchase to get the 5 min run time? I
assumed about a 10-20 amp continuous average draw... Do you have and suggestions
on companies or specific products that would work for this application?"
My advice is to look up batteries in the yellow pages to find a battery
specialist. Interview a few to find one you like. Buy what they recommend.
That was easy advise, but is that what you wanted to hear?
There are many batteries that will do what you want. You suggest you need
to consume 100 ampere minutes. But what final voltage will you accept? Once
you decided that, you are ready to buy a battery. Plan early to figure out
how much room to leave for the battery. I bet it has to be bigger and heavier
than you expect.
WINTER BATTERY STORAGE
"Each fall I gather up the batteries from my motorcycle, riding lawnmower
and family boat and store them in my basement. I've read that it is a good
idea to charge them occasionally. I have a variable DC power supply, and I
wondered if holding them at somewhere around 13 to 14 volts all winter would
keep them charged and healthy, as batteries in vehicles are always at this
level when running."
Keep the voltage below the gassing point of the battery, about 13.8 volts.
Check the water level periodically to make sure they aren't gassing. If you
have to add water, lower the voltage a tenth.
Or - charge the battery, keep it in a cool place, charge again maybe three
Or - use our MLC6012 charger for maintaining a motorcycle, riding lawnmower
type battery over winter.
WARMING A BATTERY
"Can I warm a cold battery(sub-zero) with a 10 minute/10amp boost just
before cranking? Would this overcharging cause premature battery failure
if done on a regular basis?"
I doubt that you will notice any temperature rise on a sub-zero battery
with ten amps for ten minutes, nor do any damage. So many pounds of lead and
not enough heat. Invest in a battery warming device instead.
WHAT ABOUT THIS KIND OF BATTERY?
"What are advantages/properties of nickel hydride? Thank you!"
Check out the news group, sci.chem.electrochem.battery. Questions like
yours are answered there all the time.
WORN OUT BATTERY
"Your instructions are very detailed, however, I have a deeply discharged
battery. It was left in a car in storage. The eye is dark, but not clear
or yellow. After about two hours charge time I noticed that the battery sounds
like it is boiling lightly. The battery is not warm, about room temperature.
Is this normal? I have stopped charging the battery and waiting for a response.
If this is normal, it may be a good idea to add it to your instructions. Or
at least some idea what might be normal to expect during charging. Thank you
for your time."
Typically a battery left in a discharged state for a long time needs to
be replaced. I have an old car with the same problem. Instead of taking a
charge, the battery voltage just rises rapidly to the point where the water
breaks down into hydrogen and oxygen. That's the bubbling you hear. Continuing
on really does no good. Time for a new battery.
Usually when you try to charge a battery like this the current on the
ammeter is very low, or maybe starts high and falls rapidly - showing that
the battery isn't charging. This is an example of a worn out battery with
sulfated plates mentioned at the end of our instruction manual.
HOW MUCH POWER DOES MY ALTERNATOR USE?
"I enjoy your home page. How much power (horse power) is needed to spin
a 50 amp alternator? A 100 amp alternator? Also, what rpm is needed for these
I have no idea. But you could make an estimate. A 100 amperes at say 13
volts is 1300 watts. Look up how many watts are in 1 horsepower and divide
it out. Add a little extra for mechanical losses and you'll be close. However
the power required will be high if the alternator is providing it's full
output to a battery and lower when it's providing small currents. So the
power required to spin depends on the electrical load. Why not see if your
car manufacturer has a web page and ask them.
General battery and charging safety information
may be found in our instruction manual.
Answers to a lot of common questions are found there.
SOME LITTLE BATTERY TIPS
Hot weather is hard on batteries. Park in the shade. I talked to a man
who parked his car in the sun on a very hot day in Phoenix, Arizona and
found that his battery had exploded. He needed a new hood. His dealer said
he wasn't the only one. He put a thermometer on the new hood to see how hot
it could get. He said the thermometer went off scale at 200 degrees F. While
only a few batteries will blow up at high temperatures, they all may be damaged
by the heat. Their useful life will be shorter and their capacity reduced.
Which means the car will be harder to start in cold weather.
Cold weather makes batteries sluggish. The chemical reaction in the battery
that produces the electricity slows down in the cold. Cold batteries resist
being charged - require a longer than normal charging time. Short trips (less
than 30 minutes) in stop and go traffic during cold weather may not give
the alternator enough time to put back the electricity used in the trip. If
the next morning is going to be unusually cold, charge your battery the night
Newer cars have one or more on-board computer systems that use electricity
even when the car is not running. If your car is unused for a few weeks the
computer can run the battery down (idle batteries also will slowly discharge
themselves) to the point where your car won't start. We make float chargers
that will keep up the battery of a seldom used car.
Auto makers are using smaller batteries to save weight to meet government
regulations for increased gas mileage. Down sized batteries are made lighter
by reducing the amount of lead in the battery plates. They can still start
your car, but if your alternator fails, a smaller(lighter) battery will not
give the range of a larger(heavier) one.
In cold weather the power available from a fully charged battery is less
than half of what is available in warm weather. The engine is harder to start
because the oil is stiffer in the cold. Driving in winter means you often
are taking more out of your battery that you are putting in: lights on; heater;
rear window defroster; wipers running. If your battery isn't fully charged,
it may not be able to start the engine. What to do? Charge the battery once
a week. Keep the battery warm. Park in a heated garage. In very cold
climates use an engine heater when parked. A battery heater also may make
the difference between starting and not.
For further information about: our catalog products, a special application
you may have,
or to order, contact:
Jonathan Chaiken (extension 12) firstname.lastname@example.org
Schauer Battery Charger Company.
3210 Wasson Rd
Cincinnati, OH 45209 USA
phone: 800-899-VOLT toll free
general e-mail to the company by writing to:
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