click here to download SULFATION GUIDE - 1 page

Sulfation – Why it may be killing your battery
It has long been known that Golf Car as well as other application lead-acid batteries, sealed AGM or
flooded (wet cell-filler caps), when used infrequently, lose power and have shorter lives than those used on a more
regular-daily basis. Why should this be? It is counter-intuitive. Something else must be going on that is not seen
or readily understood. The major “unseen” is “sulfation”, a build-up of lead sulfate crystals causing “bad things”
to begin happening leading to loss of cranking power, longer charging times, excessive heat build-up leading to
“boil out”, shorter running times between charges and lastly, dramatically shorter battery life. It is however, not
the only reason a battery fails.
Because there are numerous causes of battery failure, it is difficult to determine the present “health” of
a failing battery. It is long known and widely accepted that the single largest cause of early battery failure is
“sulfation”. It is however not the only cause. The job of a VDC Electronics or any company concerned with
helping extend the usefulness of batteries, is to accurately guide the user in determining whether desulfating his
battery will bring it back to “good” health. There are conditions that exist that render a battery beyond “recover”.
These cannot be easily determined, without destroying the battery in the process. Thus, at times, desulfating it
won’t make it “good” again. Do we just tell the owners of the hundreds of thousands of batteries that can be
“saved” from early failure, due to sulfation, to not even “give it a shot”? Seven (7) years of producing more than
forty thousand (40,000) charger-maintainer-desulfator units per year, tells us we should not stop our efforts. Can
we do a better job? We can always do a better job, so long as we continue to have the desire and knowledge to do
Conclusion: de-sulfating batteries, via high frequency-high energy electronic pulses works at removing
sulfate from any type lead-acid battery, sealed or wet cell. By doing so, otherwise healthy batteries, those which
have lost no more than 20% of their power*, can expect improvement to an 85% or greater level of performance.
As with our own bodies, prevention beats rehab, every time. With BatteryMINDers’ ability to fully charge,
without ever overcharging, no matter how long left connected, there is no reason sulfation should ever become an
issue. Further, without sulfation ever reaching damaging levels and the battery never subjected to overcharging,
life and performance can be expected to be several folds better than any battery left to self-discharge, as is typical
of so many golf car batteries. “The proper use of a non-Aircraft Specific BatteryMINDer ensures the longest
performance life of any golf car battery, sealed or wet (filler caps). Our unconditional Guarantee and 5-year full
parts and labor warranty, should tell most that, we ‘walk the walk’”.
*As determined by electrolyte specific gravity and/or no load battery voltage after “resting” battery for 10-12 hours.

click here to download FAQ GUIDE - 27 pages




A word of caution: Lead-acid batteries contain a sulfuric acid electrolyte, which is
a highly corrosive poison and will produce gasses when recharged and explode if
ignited. This will hurt you--BAD! When working with batteries, you need to have
plenty of ventilation, remove your jewelry, wear protective eyewear (safety
glasses) and clothing, and exercise caution. Do not allow battery electrolyte to
mix with salt water. Even small quantities of this combination will produce
chorine gas that can KILL you! Whenever possible, please follow the
manufacturer's instructions for testing, jumping, installing, charging and
equalizing batteries.
This FAQ assumes a 12-volt, six cell, negative grounded, lead acid battery found
in most recreational applications in North America. For six-volt batteries, divide
the voltage by two; for eight-volt batteries, divide by 1.5; for 24-volt batteries,
double the voltage; and for 48-volt batteries, multiple by four.
1.1. Remove the surface charge before testing and check specific gravity in
each cell. (Please see Section 3.)
1.2. Buy the freshest and largest ampere-hour battery that will fit your
requirements. (Please see Section 4.)
1.3. Perform preventive maintenance, especially during hot weather. (Please
see Section 7.7.)
1.4. Shallower the average discharge, the longer the total battery life.
(Please see Section 7.5.)
1.5. Temperature matters! Heat kills batteries and cold reduce the available
Because only the rich can afford cheap batteries.....
A good quality deep cycle lead acid battery will cost between $50 and $200 and,
if properly maintained, will give you at least 150 deep discharge cycles. The
purpose of a deep cycle battery is to provide power for trolling motors, golf carts,
fork lift trucks, uninterruptible power supplies (UPS), and other accessories for
marine and recreational vehicle (RV), commercial and stationary applications.
Dead batteries almost always occur at the most inopportune times: across the
lake, during bad weather, or on the 17th tee.
2.1. How is a battery made?
There is an excellent description of how battery is made at the Battery
Council International (BCI) web site at
http://www.battery.council.org/made.html. A twelve-volt car battery is
made up of six cells, each producing 2.1 volts and that are connected in
series from positive to negative. Each cell is made up of an element
containing positive plates that are all connected together and negative
plates, which are also all connected together. They are individually
separated with thin sheets of electrically insulating, porous material
“envelopes” [labeled #3 in the diagram below] that are used as spacers
between the positive (usually light orange) and negative (usually slate
gray) plates to keep them from electrically shorting to each other. The
plates [#2 in the diagram below], within a cell, alternate with a positive
plate, a negative plate and so on. A plate is made up of a metal grid that
serves as the supporting framework for the active porous material that is
“pasted” on it. In Europe, using solid lead positive “Plante” plates is
[Source: BCI]
After the “curing” of the plates, they are made up into cells, and the cells
are inserted into a high-density tough polypropylene or hard rubber case
[#1 in the diagram above]. The cells are connected to the terminals [#5 in
the diagram above], and the case is covered and then filled with a dilute
sulfuric acid electrolyte [#4 in the diagram above]. The battery is initially
charged or “formed” to convert yellow Lead Oxide (PbO or Litharge) into
Lead Peroxide (PbO2), which is usually dark brown or black. The
electrolyte is replaced and the battery is given a finishing charge. Some
batteries are “dry charged” meaning that the batteries are shipped without
electrolyte and it is added and recharged when they are put into service.
[Source: BCI]
Two important considerations in battery construction are porosity and
diffusion. Porosity is the pits and tunnels in the plate that allows the
sulphuric acid to get to the interior of the plate. Diffusion is the spreading,
intermingling and mixing of one fluid with another. When you are using
your battery, the fresh acid needs to be in contact with the plate material
and the water generated needs to be carried away from the plate. The
larger the pores or warmer the temperature, the better the diffusion.
2.2. How does a battery work?
[Source: BCI]
A more detailed description of how a battery works can be found on the
BCI web site at http://www.batterycouncil.org/works.html. A battery is
created by alternating two different metals such as Lead Dioxide (PbO2),
the positive plates, and Sponger lead (Pb), the negative plates. Then the
plates are immersed in diluted Sulfuric Acid (H2SO4 ), the electrolyte. The
types of metals and the electrolyte used will determine the output of a
cell. A typical lead-acid battery produces approximately 2.1 volts per cell.
The chemical action between the metals and the electrolyte creates the
electrical energy. Energy flows from the battery as soon as there is an
electrical load, for example, a starter motor that completes a circuit
between the positive and negative terminals. The electrical current flows
as charged portions of acid (ions) between the battery plates and as
electrons through the external circuit. The action of the lead-acid storage
battery is determined by chemicals used, State-of-Charge, temperature,
porosity, diffusion, and load determine the action of the lead-acid storage
2.3. Why do batteries die?
In cold climates, a battery normally “ages” as the active positive plate
material sheds (or flakes off) due to the expansion and contraction that
occurs during the discharge and recharge cycles. A brown sediment,
sludge or “mud,” builds up in the bottom of the case and can short the cell
out. In hot climates, additional causes of failure are positive grid growth,
positive grid metal corroding in the electrolyte, negative grid shrinks,
plates buckling, and loss of water. Deep discharges, heat, vibration, over
charging, under charging and non-usage accelerate this “aging” process.
Another major cause of premature battery failure is lead sulfation. Please
see Section 12 for more information on sulfation. Using tap water to refill
batteries can produce calcium sulfate, which also will coat the plates and
fill pores. Recharging a sulfated battery is like trying to wash your hands
with gloves on. When the active material in the plates can no longer
sustain a discharge current, and the battery “dies”.
Most of the “defective” batteries returned to manufacturers during free
placement warranty periods are good. This suggests that most sellers of
new batteries do not know how to or fail to take the time to properly load
test or recharge them.
There are six simple steps in testing a deep cycle battery: inspect, recharge,
remove surface charge, measure the state-of-charge, load test, and recharge. If
you have a non-sealed battery, it is highly recommended that you use a good
quality temperature compensated hydrometer; these can be purchased at an
auto parts store for between $5 and $20. A hydrometer is a float type device
used to determine the state-of-charge by measuring the specific gravity of the
electrolyte in each cell. It is a very accurate way of determining a battery's stateof-
charge and its weak or dead cells. To troubleshoot charging or electrical
systems or if you have a sealed battery, you will need a digital voltmeter with
0.5% or better accuracy. A digital voltmeter can be purchased at an electronics
store like Radio Shack for between $20 and $200. Analog voltmeters are not
accurate enough to measure the millivolt differences of a battery's state-ofcharge
or the output of the charging system. The purchase of a battery load
tester is optional; if you use a golf cart or electric trolling motor every day, buy
one. A more accurate way of testing the capacity of a lead acid battery is by
using a conductance tester, such as a Midtronics.
Visually inspect for obvious problems. For example, is there a loose or
broken alternator belt, electrolyte levels below the top of the plates,
corroded or swollen cables, corroded terminal clamps, dirty or wet battery
top, loose hold-down clamps, loose cable terminals, or leaking or
damaged battery case?
If the electrolyte levels are low in non-sealed batteries, allow the battery to
cool and add distilled water to the level indicated by the battery
manufacturer. If this is not indicated, use 1/4 inch (7 mm) below the
bottom of the plastic filler tube (vent wells). The plates need to be covered
at all times. Avoid overfilling, especially in hot climates, because heat will
cause the electrolyte to expand and overflow.
Recharge the battery to 100% state-of-charge. If the battery has a
difference of .03 specific gravity reading between the lowest and highest
cell, then you should equalize it. (Please see Section 6.)
Surface charge is the uneven mixture of sulfuric acid and water within the
surface of the plates as a result of charging or discharging. It will make a
weak battery appear good or a good battery appear bad. You need to
eliminate the surface charge by one of the following methods:
3.3.1. Allow the battery to sit for four to twelve hours to allow for the
surface charge to dissipate.
3.3.2. Apply a load that is 33% of the ampere-hour capacity for five
minutes and wait five to ten minutes.
3.3.3. With a battery load tester, apply a load of at least one half the
battery's CCA rating for 15 seconds and wait five to ten minutes.
If the battery's electrolyte is above 110° F (43.3° C), allow it to cool. To
determine the battery's state-of-charge with the battery's electrolyte
temperature at 80° F (26.7° C), use the following table. The table
assumes that a 1.265 specific gravity reading is a fully charged, wet, lead
acid battery. For other electrolyte temperatures, use the Temperature
Compensation table below to adjust the Open Circuit Voltage or Specific
Gravity readings. The Open Circuit Voltage will vary for gel cell and AGM
type batteries, so check the manufacturer's specifications.
Open Circuit
Average Cell
12.65 100% 1.265 -75° F
(-59.4° C)
12.45 75% 1.225 -55° F
(-48.3° C)
12.24 50% 1.190 -34° F
(-36.7° C)
12.06 25% 1.155 -16° F
(-26.7° C)
11.89 Discharged 1.120 -10° F
(-23.3° C)
[Source: BCI]
Add or
Subtract to
SG Reading
Add or
Subtract to
160° 71.1° +.032 +.192
150° 65.6° +.028 +.168
140° 60.0° +.024 +.144
130° 54.4° +.020 +.120
120° 48.9° +.016 +.096
110° 43.3° +.012 +.072
100° 37.8° +.008 +.048
90° 32.2° +.004 +.024
80° 26.7° 0 0
70° 21.1° -.004 -.024
60° 15.6° -.008 -.048
50° 10° -.012 -.072
40° 4.4° -.016 -.096
30° -1.1° -.020 -.120
20° -6.7° -.024 -.144
10° -12.2° -.028 -.168
0° -17.8° -.032 -.192
Electrolyte temperature compensation, depending on the battery
manufacturer's recommendations, will vary. If you are using a nontemperature
compensated HYDROMETER, make the adjustments
indicated in the table above. For example, at 30° F (-1.1° C), the specific
gravity reading would be 1.245 for a 100% State-of-Charge. At 100° F
(37.8° C), the specific gravity would be 1.273 for 100% State-of- Charge.
This is why using a temperature compensated hydrometer is highly
recommended and more accurate than other means. If you are using a
DIGITAL VOLTMETER, make the adjustments indicated in the table
above. For example, at 30° F (-1.1° C), the voltage reading would be
12.53 for a 100% State-of-Charge. At 100° F (37.8° C), the voltage would
be 12.698 for 100% State-of-Charge.
For non-sealed batteries, check the specific gravity in each cell with a
hydrometer and average the readings. For sealed batteries, measure the
Open Circuit Voltage across the battery terminals with an accurate digital
voltmeter. This is the only way you can determine the State-of-Charge.
Some batteries have a built-in hydrometer, which only measures the
State-of-Charge in one of its six cells. If the built-in indicator is clear or
light yellow, then the battery has a low electrolyte level and should be
refilled and recharged before proceeding. If sealed, the battery is toast
and should be replaced. If the State-of-Charge is below 75% using either
the specific gravity or voltage test or the built-in hydrometer indicates
“bad” (usually dark), then the battery needs to be recharged
beforeproceeding. You should replace the battery, if one or more of the
following conditions occur:
3.4.1. If there is a .05 (sometimes expressed as 50 “points”) or more
difference in the specific gravity reading between the highest and
lowest cell, you have a weak or dead cell(s).
3.4.2. If the battery will not recharge to a 75% or more state-of-charge
level or if the built-in hydrometer still does not indicate “good” (usually
green, which is 65% state-of-charge or better).
If you know that a battery has spilled or “bubbled over” and the
electrolyte has been replaced with water, you can replace the old
electrolyte with new electrolyte and go back to Step 3.2 above. Battery
electrolyte is a mixture of 25% sulfuric acid and distilled water. It is
cheaper to replace the electrolyte than to buy a new battery.
3.4.3. If digital voltmeter indicates 0 volts, you have an open cell.
3.4.4. If the digital voltmeter indicates 10.45 to 10.65 volts, you probably
have a shorted cell or a severely discharged battery. A shorted cell is
caused by plates touching, sediment (“mud”) build-up or “ treeing”
between the plates.
If the battery is fully charged or has a “good” built-in hydrometer indication,
then you can test the capacity of the battery by applying a known load and
measuring the time it take to discharge the battery until 20% capacity is
remaining. Normally a discharge rate that will discharge a battery in 20
hours can be used. For example, if you have an 80-ampere-hour rated
battery, then a load of four amps would discharge the battery in
approximately 20 hours (or 16 hours down to the 20% level). New
batteries can take up to 50 charge/discharge cycles before they reach
their rated capacity. Depending on your application, batteries with 80% or
less of their original capacity are considered to be bad.
If the battery passes the load test, you should recharge it as soon as
possible to restore it to peak performance and to prevent lead sulfation.
4.1. Ampere-Hour (or Reserve Capacity) Rating
The most important consideration in buying a deep cycle battery is the
Ampere-Hour (AH) or Reserve Capacity (or Reserve Minutes) rating that
will meet or exceed your requirements and how much weight you can
carry. Most deep cycle batteries are rated in discharge rates of 100 hours,
20 hours, or 8 hours. The higher the discharge, the lower the capacity
due to the Peukert Effect and the internal resistance of the battery.
Reserve Capacity (RC) is the number of minutes a fully charged battery at
80° F (26.7° C) is discharged at 25 amps before the voltage falls below
10.5 volts. To convert Reserve Capacity (RC) to Ampere-Hours at the 25
amp rate, multiple RC by .4167. More ampere-hours (or RC) are better in
every case. Within a BCI group size, the battery with higher amperehours
(or RC) will tend to have longer lives and weigh more because of
thicker plates and more lead.
The following graph shows the effects of temperature on the capacity of a
[Source: Concorde]
If more ampere-hours are required, two new and identical six-volt batteries
can be connected in series (positive terminal of Battery One to the
negative terminal of Battery Two). Two (or more) new and identical 12-
volt batteries can be connected in parallel. If you connect two 12-volt
batteries in parallel and they are identical in type, age and capacity, you
can potentially double you original capacity. If you connect two that are
not the same type, you will either overcharge the smaller of the two, or you
will undercharge the larger of the two.
The recommended parallel and series connections are as follows:
[Source: Interstate Batteries]
When connected this way, the batteries will discharge and recharge
equally. When connecting in series or parallel and to prevent recharging
problems, do not mix old and new batteries or ones of different types.
Cable lengths should be kept short and cable must be sized large enough
to prevent significant voltage drop; there should be a maximum of 0.2 volts
(200 millivolts) or less drop between batteries.
4.2. Type
Car batteries are especially designed for high initial cranking amps
(usually 200 to 400 amps for five to 15 seconds) to start a car and for
shallow (10% or less) discharges. They are not designed for deep cycle
discharges. Deep cycle (and marine) batteries are designed for prolonged
discharges at lower current and not for high current discharges. The
plates in a car battery are more porous and thinner than in deep cycle
batteries and use sponges or expanded metal grids instead of solid lead.
A deep cycle battery will typically outlast two to ten car batteries when
used in deep cycle applications. In warm weather, starting an engine will
typically consume less that 5% of a car battery's capacity. In contrast,
deep cycle (or marine) batteries are used for applications that will
consume between 20 and 80% of the battery's capacity.
A “dual” or starting marine battery is a compromise between a car and a
deep cycle battery that is specially designed for marine applications. A
deep cycle or “dual marine” battery will work as a starting battery if it can
produce enough current to start the engine, but not as well as a car
battery. For saltwater applications, AGM or gel cell batteries are highly
recommended to prevent chorine gas.
For RVs, a car battery is normally used to start the engine and a deep
cycle battery is used to power the RV accessories. The batteries are
connected to a diode isolator. When the RV's charging system is running,
both batteries are automatically recharged. An excellent and easy to
understand free booklet on multi-battery applications, “Introduction to
Batteries and Charging Systems”, can be downloaded from
http://www.surepower.com/ebrochures.html or obtained by calling
(800) 845-6269 or (503) 692-5360.
The two most common types of deep cycle batteries are flooded (also
known as wet or liquid electrolyte) cell and valve regulated (VR). These
types are divided into Marine and RV batteries. There are 50% depth-ofdischarge
limits and sponge lead plates batteries, and there are the more
expensive Deep Cycle (traction and stationary) batteries with 80% depthof-
discharge limits, solid lead plates, and longer lives.
4.2.1. Flooded (Wet) Cell
Flooded cell deep cycle batteries are divided, like their car battery
counterparts, into low maintenance (the most common) and
maintenance free (or sealed), which is based on their plate
formulation. Low maintenance batteries have lead-antimony/antimony
or lead-antimony/calcium (dual alloy or hybrid) plates; the maintenance
free batteries use lead-calcium/calcium. The advantages of
maintenance free batteries are less preventive maintenance, up to
250% less water loss, faster recharging, greater overcharge
resistance, reduced terminal corrosion, up to 40% more life cycles, and
up to 200% less self discharge. However, they are more prone to
deep discharge (dead battery) failures due to increased shedding of
active plate material and development of a barrier layer between the
active plate material and the grid metal. Further, if sealed, they tend to
have a shorter life in hot climates because lost water cannot be
replaced. Automobile industry liability lawyers prefer this type of
battery because consumers are less likely to be injured. Finally,
maintenance free batteries are generally more expensive than low
maintenance batteries.
4.2.2. Valve Regulated
Gas-recombinant Valve Regulated Lead-Acid (VRLA) batteries are
generally divided into two groups, gel cell and Absorbed Glass Mat
(AGM). VRLA batteries are spill proof, so they can be used in semienclosed
areas, are totally maintenance free, and have a longer shelf
life. Their greatest disadvantage is the high initial cost (two to three
times) but arguably can have an overall lower total cost of ownership
due to a longer lifetime and no “watering” labor costs, only if they are
properly maintained and recharged.
[Source: Hawker]
4.3. Size and Terminals
In North America, a Battery Council International (BCI) group number
(e.g., U1, 24, 27, 31, 8D, etc.) is based on the physical case size, terminal
placement and terminal polarity. In Europe, the EN, IKC, Italian CEI, and
German DIN standards are used and in Asia, the Japanese JIS standard
is used. Within a group, the ampere-hour or RC ratings, warranty and
battery type will vary in models of the same brand or from brand to brand.
You can also find BCI size information online at
http://www.exidebatteries.com/bci.cfm. Generally, batteries are sold by
model, and some of the group numbers are sold for the same price. This
means that for the same money you can potentially buy a physically larger
battery with more ampere-hour or RC than the battery you are replacing.
Be sure that the replacement battery will fit, the cables will correct to the
correct terminals, and that the terminals will not touch anything else.
There are six types of battery terminals: SAE Post, GM Side, “L”, Stud,
combination SAE and Stud, and combination SAE Post and GM Side. For
automotive applications, the SAE Post is the most popular, followed by
GM Side and then the combination “dual” SAE Post and GM Side. “L”
terminal is used on some European cars, motorcycles, lawn and garden
devices, snowmobiles, and other light duty vehicles. Stud terminals are
used on heavy duty and deep cycle batteries. The positive SAE Post
terminal is slightly larger (by 1/16”) than the negative one. Terminal
locations and polarity will vary.
4.4. Freshness
Determining the “freshness” of a battery is sometimes difficult. Never buy
a non-sealed wet lead-acid battery that is more than three months old or
a sealed wet lead-acid battery that is more than six months old. This is
because by then it has started to sulfate unless it has periodically been
recharged (this is not the usual practice of many retailers) or it is “dry
charged”. The exceptions to this recommendation are AGM and Gel Cell
batteries, which can be stored up to 12 months before the state-of-charge
drops 80% or below. Please see Section 12 for more information on
sulfation. Dealers will often place their older batteries in storage racks so
they will sell first. The new batteries can often be found in the rear of the
rack or in a storage room. The date of manufacture is stamped on the
case or printed on a sticker.
Some of the manufacturer's date coding techniques are as follows:
4.4.1. Delphi (AC Delco and some Sears DieHard)
Dates are stamped on the cover near one post. The first number is the
year. The second character is the month A-M, skipping I. The last two
characters indicate geographic areas. Example 0BN3=2000 February.
[Source: Interstate Batteries]
4.4.2. Douglas
Douglas uses the letters of their name to indicate the year of
manufacture and the digits 1-12 for the month. D=1994 O=1995
U=1996 G=1997 L=1998 A=1999 S=2000 Example S02=2000 Feb.
4.4.3. East Penn, GNB (Champion), and Johnson Controls Inc. (Interstate
and some Sears DieHard)
Usually on a sticker or hot-stamped on the side of the case.
A=January, B=February, and the letter I is skipped. The number next
to the letter is the year of shipment. Example B0=Feb 2000
[Source: Interstate Batteries]
4.4.4. Exide (some Sears non-Gold DieHards)
The fourth or fifth character is the month. The following numeric
character is the year. A-M skipping I. Example RO8B0B=Feb. 2000.
[Source: Interstate Batteries]
4.4.5. Trojan
Stamp on post, 2 Months after manufacture date.
If you cannot determine the date code, ask the dealer or contact the
manufacturer. Like bread, fresher is definitely better and does matter.
4.5. Warranty
As with tire warranties, battery warranties are not necessarily indicative of
the quality or cost over the life of the battery. Some dealers will prorate
warranties based on the list price of the bad battery, so if a battery failed
half way or more through its warranty period, buying a new battery
outright might cost you less than paying the difference under a prorated
warranty. The exception to this is the free replacement warranty and
represents the risk that the manufacturer is willing to assume. A longer
free replacement warranty period is better.
5.1. Thoroughly wash and clean the old battery, battery terminals and case
or tray with warm water to minimize problems from acid or corrosion.
Heavy corrosion can be neutralized with a mixture of one pound of baking
soda to one gallon of warm water. Wear safety goggles and, using a stiff
brush, brush away from yourself. Also, mark the cables so you do not
forget which one to reconnect.
5.2. Turn off all electrical switches in the vehicle and shut off the ignition
switch. Disable any alarm systems. Remove the NEGATIVE cable first
because this will minimize the possibility of shorting the battery when you
remove the other cable. Secure the negative cable so that it cannot
"spring" loose and make electrical contact. Next remove the POSITIVE
cable and then the hold-down bracket or clamp. If the hold down bracket
is severely corroded, replace it. Dispose of the old battery by exchanging
it when you buy your new one or by taking it to a recycling center.
According to BCI, over 96% of the old battery lead is recycled, making
batteries one of the most completely recycled of all recycled items.
Please remember that batteries contain large amounts of harmful lead and
acid, so please dispose of your old battery properly for safety and to
protect our fragile environment.
[Source: BCI
5.3. After removing the old battery, be sure that the battery tray or box and
cable terminals or connectors are clean. Auto parts stores sell a cheap
wire brush that will allow you to clean the inside of terminal clamps and
the terminals. If the terminals, cables or hold-down brackets are severely
corroded, replace them. Corroded terminals or swollen cables will
significantly reduce starting capability.
5.4. Use paraffin oil-soaked felt washer pads found at auto parts stores or
thinly coat the terminal, terminal clamps and exposed metal around the
battery with a high temperature grease or petroleum jelly (Vaseline) to
prevent corrosion. Do not use the felt or metal washers between the
mating conductive surfaces with side, stud or "L" terminal batteries. Use
of stainless steel and other metal washers and bolts have also caused
problems with electrolysis and high resistance.
5.5. Place the replacement battery so that the NEGATIVE cable will connect
to the NEGATIVE (-) terminal. Reversing the polarity of the electrical
system will severely damage DESTROY it. It can even cause the battery
to explode.
5.6. After replacing the hold-down bracket, reconnect the cables in reverse
order, i.e., attach the POSITIVE cable first and then the NEGATIVE cable
5.7. Before using the battery, check the electrolyte levels and add distilled
water to cover the plates. Check the state-of-charge and recharge if
necessary. Then recheck the electrolyte levels after the battery has
cooled and top off with distilled water as required, but do not overfill.
6. not available
The typical life of a deep cycle battery is:
Starting (Used as a deep cycle) 0 to 12 months
Marine to 6 years
Golf Cart to 6 years
Gelled Deep Cycle to 8 years
AGM to 10 years
Ni-Cad to 10 years
Telecommunications (Float) to 10 years
Fork Lift to 10 years
Industrial (Traction) to 20 years
Industrial (Stationary) to 20 years
Ni-Fe to 20 years
7.1. Recharging slowly and keeping your battery well maintained are the
best ways to extend the life of your battery.
7.2. Recharge a deep cycle battery as soon as possible after each use to
prevent sulfation.
7.3. In warmer climates and during the summer, “watering” is required more
often. Check the electrolyte levels and add distilled water, if required.
Never add electrolyte to a battery that is not fully charged'just add distilled
water and do not overfill. The plates must be covered at all times.
7.4. High ambient temperatures (above 80%deg; F [26.7° C]) will shorten
battery life because it increases positive grid corrosion and growth.
7.5. Shallower the average depth-of-discharge (DoD), increases the battery
life. For example, a battery with an average of 50% DoD will last twice as
long or more as an 80% DoD; a 20% DoD battery will last five times longer
than a 50% DoD. For example, golf cart batteries will average 225 cycles
at 80% DoD and increase to 750 cycles at 50% DoD. Try to avoid DoD
that is less than 10% or greater than 80%. Industrial traction and
stationary deep cycle batteries are designed for 80% DoD and most
marine an RV deep cycle batteries are designed for 50% DoD.
Depth-of-Discharge (DoD)
[Source: Concorde]
7.6. When in storage, recharging when the state-of-charge drops to 80% or
below will prevent lead sulfation.
7.7. Maintaining the correct state-of-charge while in storage, electrolyte
levels, tightening loose hold-down clamps and terminals, and removing
corrosion is normally the only preventive maintenance required for a deep
cycle battery.
7.8. Avoid “opportunity charging." Size the battery so that there is a minimum
of one cycle per day.
7.9. Never discharge below 10.5 volts.
8.1. Loss of electrolyte due to heat or overcharging.
8.2. Lead sulfation.
8.3. Undercharging.
8.4. Old age (positive plate shedding) or “Sludging”.
8.5. Excessive vibration.
8.6. Freezing or high temperatures.
8.7. Using tap water which causes calcium sulfation.
8.8. Positive grid corrosion or growth due to high temperatures.
8.9. Fast recharging at rates greater than C/10.
Batteries naturally self-discharge 1% to 15% per month while in storage, and
lead sulfation will start occurring when the state-of-charge drops below 80%. If
left in a vehicle, disconnecting the negative cable will reduce the level of
discharge by eliminating the parasitic load. Cold will slow the self-discharge
process down and heat will speed it up. Use the following six simple steps to
store your batteries:
9.1. Physically inspect for damaged cases, remove any corrosion, and clean
and dry the battery tops.
9.2. Fully recharge the batteries.
9.3. Check the electrolyte levels and add distilled water as required, but
avoid overfilling.
9.4. Store in a cold dry place, but not below 32° F (0° C).
9.5. Depending on the ambient temperature and self-discharge rate,
periodically test the state-of-charge using the procedure in Section 4.
When the state-of-charge drops below 80%, recharge the batteries using
the procedures in Section 6. An alternative would be to connect an
automatic voltage regulated, solar panel or “smart trickle” charger to “float”
batteries. Based on the manufacturer's recommendations, use an
automatic or smart charger that has been manufactured for this purpose
and battery type. You may also use a setting of 13.02 to 13.8 volts for wet
batteries and 13.2 to 14.1 volts for VRLA batteries, compensated for
temperature, and the correct automatic or smart charger that has been
designed not to overcharge the batteries.
The following graph from Concorde demonstrates the effect of
temperature on float voltage requirements.
[Source: Concorde]
9.6. Equalize only wet (flooded) or AGM batteries, when you remove the
batteries from storage; use the procedure in Section 6.
10.1. Storing a battery on a concrete floor will discharge them.
A hundred years ago when battery cases were made of porous materials,
such as wood, storing batteries on concrete floors would accelerate their
discharge. Modern battery cases, made of polypropylene or hard rubber,
which are better sealed, so external leakage, causing discharge, is no
longer a problem. However, the top of the battery must be clean and dry.
Temperature stratification within large batteries could accelerate the
internal “ leakage” or self-discharge if the battery is sitting on a cold floor in
a warm room or is installed in a submarine.
10.2. Driving a car will fully recharge a battery.
Some of factors affecting a car charging system's ability to charge a
battery are: how much current from the alternator is diverted to the battery
to charge it, how long the current is available and the temperature.
Generally, idling the engine or on short “stop-and-go trips” during bad or
hot weather or at night will not recharge a battery. A long daytime trip in
warm weather should recharge a battery.
10.3. A battery will not explode.
Recharging a wet lead-acid battery normally produces hydrogen and
oxygen gasses. While spark retarding vent caps help prevent battery
explosions, they occur when jumping, connecting or disconnecting charger
or battery cables, and starting the engine. While not fatal, battery
explosions cause thousands of eye and burn injuries each year.
When battery explosions occur when starting an engine, here is the usual
sequence of events: One or more cells had a high concentration of
hydrogen gas (above 4.1%) because the vent cap was clogged or a
defective valve did not release the gas. The electrolyte levels fell below
the top of the plates due to high under hood temperatures, overcharging,
or poor maintenance. A low resistive bridge or “treeing” formed between
the top of the plates such that when the current started to flow, it caused
an arc or spark in one of the cells. That combination of events ignites the
gas, blows the battery case cover off and spatters electrolyte all over the
engine compartment. The largest number of battery explosions while
starting an engine occurs in hot climates.
When an explosion happens, thoroughly rinse the engine compartment
with water, and then wash it with a solution of one-pound baking soda to
one gallon of warm water to neutralize the residual battery acid. Then
thoroughly rewash the engine compartment with water. Periodic
preventive maintenance (please see Section 7.7.), working on batteries in
well ventilated areas or using Valve Regulated Lead Acid (AGM or gel
cell) type batteries can significantly reduce the possibility of battery
10.4. A battery will not lose its charge sitting in storage.
Depending on the type of battery, it has natural self-discharge or internal
electrochemical “leakage” at a 1% to 15% rate per month that will cause it
to become sulfated and fully discharged over time. Higher temperatures
accelerate this process. A battery stored at 95° F (35° C) will self
discharge twice as fast than one at 75° F (23.9° C). (Please see
Section 9.)
10.5. Maintenance free batteries never require maintenance.
In hot climates, water in the electrolyte is “decomposed” due to the high
temperatures and normal charging of a wet maintenance free battery.
Water can also be lost due to excessive charging voltage or charging
currents. Non-sealed batteries are recommended in hot climates so they
can be refilled with distilled water when this occurs. Please see
Section 7.7. for other preventive maintenance that should be performed on
“maintenance free” batteries.
10.6. Test the alternator by disconnecting the battery with the engine
A battery as like a voltage stabilizer or filter to the pulsating DC produced
by the charging system. Disconnecting a battery while the engine is
running can destroy sensitive electronic components, for example,
emission computer, audio system, cell phone, alarm system, etc., or even
the charging system itself. These damages can occur because the
voltage can rise to 40 volts or more. In the 1970s, removing a battery
terminal was an accepted practice to test charging systems of that era.
That is not the case today. Just say NO if anyone suggests this.
10.7. On really cold days turn your headlights on to “warm up” the
battery up before starting your engine.
While there is no doubt that turning on your headlights will increase the
current flow in a car battery; it also consumes valuable capacity that could
be used to start the engine. Therefore, this is not recommended. For
extremely cold temperatures, externally powered battery warmers, battery
blankets, or engine block heaters are highly recommended. AGM and Ni-
Cad batteries perform better in extremely cold temperatures than wet cell
10.8. Batteries last longer in hot climates than in cold ones.
Batteries last approximately two thirds as long in hot climates as cold
ones. Heat kills batteries, especially sealed wet lead acid batteries.
10.9. Deep cycle batteries have a memory.
Lead acid deep cycle batteries do not have the so called “memory effect”
that first generation Ni-Cad batteries have.
Discharging, like charging, depends on a number of factors such as: the initial
state-of-charge, depth-of-discharge, age, capacity of the battery, load and
temperature. For a fully charged battery at 70° F (21.1° C), the ampere-hour
rating divided by the load in amps will provide the estimated life of that cycle. For
example, a new, 72-ampere-hour battery with a 10-amp load should last
approximately 7.2 hours. As the battery ages, the capacity is reduced.
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