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Old 05-26-2004, 04:00 PM   #15
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Battery FAQ (long)/Part1

Lots of info about batteries and self discharging. I picked this up from a Google Post. Enjoy!



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) and commercial applications.

A twelve volt deep cycle battery is made up of six cells, each producing 2.1 volts that are connected in series 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 that are used as
spacers between the positive and negative plates to keep them from shorting to each other. The plates, 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 material which is "pasted" on it. The cells are inserted into a polypropylene case, connected to the terminals, covered, filled with a dilute sulfuric acid electrolyte and formed (initially charged). The electrolyte is replaced and the battery is given a finishing charge.

A battery is created when two different metals such as Lead Dioxide (Pb O2), the positive plates, and Sponger lead (Pb), the negative plates, are immersed in Sulfuric Acid (H2SO4), the electrolyte. 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, that flows from the battery as soon as there is a load, such a light bulb, 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, temperature, and load.

Normally a battery "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, the positive grid metal corrodes in the electrolyte,
or the negative grid shrinks. Deep discharges, heat, vibration, over charging, or non-use accelerate this "aging" process. Sediment or "mud" builds up in the bottom of the case and the can short the cell out. Another major cause of premature battery failure is sulfation. When batteries are stored discharged or stored fully charged for over three months without being recharged, the plates slow discharge and become coated with hard and dense layer of
lead sulfate. Over time, the battery can not be recharged.

Using tap water to refill batteries can produce calcium sulfate, which also will coat the plates. 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 that are returned to the manufacturer during free placement warranty periods are good. This suggests that most sellers of new batteries do not know how or take the time to properly load test or
recharge batteries.


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 temperature compensated hydrometer, which can be purchased, at an auto parts
store 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 state-of-charge and weak or dead cells.

To troubleshoot charging or electrical systems or if you have a sealed battery, you will need a digital voltmeter with .5% (or better) accuracy. A digital voltmeter can be purchased at an electronics store,for example, Radio Shack, between $20 and $200. Analog voltmeters are not accurate enough to measure the millivolt differences of the battery's state-of-charge or the output of the charging system. A battery load tester is optional.


Visually inspect for obvious problems, for example, loose of broken alternator belt,electrolyte levels BELOW the top of the plates, corroded or swollen cables,corroded terminal clamps 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 or to 1/4 inch BELOW the bottom of the plastic filler tube (vent wells). The plates need to be covered at all times and avoid OVERFILLING, especially in hot climates, because the 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 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. [RECOMMENDED].

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 at one half the battery's CCA rating for 15 seconds and wait five to ten minutes.


If the battery's electrolyte is above 100 degrees, allow it to cool. To determine the battery's state-of-charge with the battery's electrolyte temperature at 80 degrees, use the following table, which assumes that 1.265 specific gravity reading is as fully charged battery:

Voltmeter Hydrometer
Open Circuit Approximate Average Cell
Voltage State-of-charge Specific Gravity

12.65 100% 1.265

12.45 75% 1.225

12.24 50% 1.190

12.06 25% 1.155

11.89 Discharged 1.120

[Source: Battery Council International]

[Electrolyte temperature compensation, depending on the battery manufacturer's recommendations, will vary.

If you are using a NON-temperature compensated HYDROMETER, make the following adjustments, and if the temperature of the electrolyte is BELOW 80 degrees, SUBTRACT .004 specific gravity per 10 degrees below 80 degrees FROM the Specific Gravity indicated in the table above. For example, at 30 degrees, the specific gravity reading would be 1.245 for a 100% state-of-charge. If the temperature of the electrolyte is ABOVE 80 degrees, then ADD .004 specific gravity per 10 degrees above 80 degrees TO the Specific Gravity. For example, at 100 degrees,
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.

If you are using a digital VOLTMETER, then from the table above make the following adjustments, if the temperature of the electrolyte is BELOW 80 degrees, SUBTRACT
.0012 to .028 volts (1.2 to 28 millivolts) per 10 degrees below 80 degrees from the Open Circuit Voltage indicated. For example, at 30 degrees and using 28 millivolts, the reading would be 12.51 VDC at 100% state-of-charge. If the temperature of the electrolyte is ABOVE 80 degrees, then ADD .0012 to .028 volts (1.2 to 28 millivolts) per 10 degrees above 80 degrees. For example, at 100 degrees and using 28 millivolts, the Open Circuit Voltage would be 12.71 VDC.

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. It 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.

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 BEFORE proceeding. You should replace the battery, if one or more of the following conditions occur:

3.4.1. If there is a .05 or more difference in the specific gravity reading between the highest and lowest cell, you have a weak or dead cell(s). If you are really lucky, applying an EQUALIZING charge may correct this condition. (Please see Section 6.)

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 known load and measure
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 [C/20]. For example, if you have a 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 history.


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 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 amps, 20 amps, or 8 amps.

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 degrees is discharged at 25 amps
before the voltage falls below 10.5 volts.] To convert Reserve Capacity to Ampere Hours, multiple RC by .6. For example, a battery with 120 minute RCwill have approximately 72 Ampere Hours. This means that the battery should produce one amp for 72 hours of continuous use. More ampere hours (or RC) are better in every case.

Within a BCI group size, the battery with larger ampere hours (or RC) will tend to weigh more because it contains more lead.

[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 (positive terminals to positive terminals and negative terminals to negative terminals with identical cables). When connecting in series or parallel and to prevent recharging problems, do NOT mix old and new batteries or ones with different types. Cable lengths
should be kept short and cable sized large enough to prevent significant voltage drop [.2 volts (200 millivolts) or less] between batteries.]

Jack Canavera
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Old 05-26-2004, 04:00 PM   #16
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Battery FAQ (long)/Part2

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 not for deep cycle discharges. Deep cycle (and marine) batteries are designed for
prolonged discharges at lower current. [The plates in car battery are more porous and thinner than in deep cycle batteries and use sponges or expanded metal grid instead of solid lead.] A deep cycle battery will typically
outlast two to ten car batteries when used in deep cycle applications.

Starting an engine will typically consume less that 5% of a car battery's capacity. Whereas, 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 deep cycle battery. A deep cycle or "dual marine" battery will work as starting battery if it can produce enough current to start the engine, but not as
well as a car battery.

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.

The two most common types of deep cycle batteries are flooded (also known as wet or liquid electrolyte) cell and valve regulated (VR).

4.2.1. Flooded cell

Flooded cell deep cycle batteries are divided, like their car battery counterparts, into low maintenance (the most common) and maintenance free, based on their plate formulation. [Low maintenance batteries have
lead-antimony/antimony or lead-antimony/calcium (dual alloy or hybrid) plates; whereas, the maintenance free batteries use lead-calcium/calcium.]

The advantages of maintenance free batteries are less preventative 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], and if sealed, a shorter life in hot climates because lost water can not be replaced.

Maintenance free batteries are generally more expensive than low maintenance batteries.

4.2.2. Valve Regulated

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 semi-enclosed areas, are totally maintenance free, and longer shelf life. Their greatest disadvantage is the high initial cost (two to three times), but arguably could have an overall lower
cost due to a longer lifetime and no "watering" labor costs, if properly maintained and recharged.

4.3. Size

An internationally adopted Battery Council International (BCI) group number (U1, 24, 27, 31, etc.) is based on the physical case size, terminal placement and terminal polarity. 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 Exide. Generally,
batteries are sold by model, so some of the group numbers will vary for the same price. This means that for the same price 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 terminal, and that the terminals will not touch anything else.

4.4. Freshness

Determining the "freshness" of a battery is sometimes difficult. NEVER buy
a wet lead acid battery that is MORE than THREE months old because it has starting to sulfate, unless it has periodically been recharged. [Sulfation occurs when lead sulfate can not be converted back to charged material and is created when discharged batteries stand for a long time
or from excessive water loss.] 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. It is usually a combination
of alpha and numeric characters with letters for the months starting with "A" for January (generally skipping the letter "I") and digit for the year, e.g., "J6" for September 1996. If you can not determine the date code then 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 car. Most manufacturers 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 period. This represents the risk that the manufacturer is willing to assume. A longer free replacement warranty period is better.


There are three phases of battery charging--bulk, absorption and float. The bulk stage is where you can give the battery whatever current it will accept not to exceed 20% of the ampere hour rating and that will not cause
overheating. The absorption phase is voltage-regulated current charging until the battery is fully charged. This is normally when the charging current drops off to 1% or less of the ampere hour capacity of the battery.For example, end current for a 72 ampere hour battery is .7 amps or less.

Float charging at a lower voltage is used to maintain a fully charged battery. Please refer to Section 9 for more information about storing batteries and float charging them.

Equalizing is a controlled 5% overcharge to equalize and balance the voltage and specific gravity in each cell of a wet lead acid battery. Equalizing reverses the build-up of the chemical effects like stratification where acid
concentration is greater in the bottom of the battery. It also helps remove sulfate crystals that might have built up on the plates. The frequency recommendation varies by manufacturer from once a month to once a year, 50
to 100 deep cycles, or a specific gravity difference between cells of .03 or .015 volts (15 millivolts). To equalize, fully recharge the battery. Then increase the charging voltage to the manufacturer's recommendations, or if not available, ADD 5%. Heavy gassing should start occurring. Take
specific gravity readings in each cell once per hour. Equalization has occurred once the specific gravity values no longer rise during the gassing stage.

It is important to use the battery manufacturer's charging recommendations whenever possible for optimum performance and life. In addition to the earlier cautions, here are some more words of caution:

6.2. For non-sealed batteries, check the electrolyte level and be sure it
is covering the plates and is not frozen BEFORE recharging.

6.3. Do NOT add distilled water if the electrolyte is covering the top of the plates because during the recharging process, it will warm and expand. After recharging has been completed, RECHECK the level.

6.4. Reinstall the vent caps BEFORE recharging and recharge ONLY in well ventilated areas. NO smoking, sparks or open flames while the battery is being recharged because batteries give off explosive gasses.

6.5. If your battery is an AGM or a sealed flooded type, do NOT recharge with current ABOVE 12% of the battery's RC rating (or the 20% of the ampere hour rating). Gel cells should be charged over a 20 hour period and never over the manufacturer's recommended level or 14.1 VDC.

6.6. Follow the charger manufacturer's procedures for connecting and disconnecting cables and operation to minimize the possibility of an explosion, but generally you should turn the charger OFF before connecting or disconnecting cables to a battery. Good ventilation or a fan is recommended to disperse the gasses created by the recharging process.

6.7. If a battery becomes hot (over 125 degrees) or violent gassing or spewing of electrolyte occurs, turn the charger off temporarily or reduce the charging rate.

6.8. Insure that charging with the battery in the car with an external MANUAL charger will not damage the vehicle's electrical system with high voltages. If this is even a remote possibility, then disconnect the vehicle's negative battery cable from the battery BEFORE connecting the

6.9. If you are recharging gel cell batteries, manufacturer's charging voltages can be very critical and you might need special recharging equipment. In most cases, deep cycle chargers used to recharge wet
batteries can not be used to recharge gel cell and AGM batteries because of their higher charging voltage.

Use an external constant current charger, which is set not to deliver more than 12% of the RC rating of the battery and monitor the state-of-charge.

For discharged batteries, the following table lists the recommended battery charging rates and times:

Reserve Capacity Slow Charge Fast Charge
(RC) Rating

80 Minutes or less 15 Hours @ 3 amps 5 Hours @ 10 amps

80 to 125 Minutes 21 Hours @ 4 amps 7.5 Hours @ 10 amps

125 to 170 Minutes 22 Hours @ 5 amps 10 Hours @ 10 amps

170 to 250 Minutes 23 Hours @ 6 amps 7.5 Hours @ 20 amps

Above 250 Minutes 24 Hours @ 10 amps 6 Hours @ 40 amps

[Source: Battery Council International]

The BEST method is to SLOWLY recharge the battery at 70 degrees over eight hour period using an external constant voltage (or tapered current charger) because the acid has more time to penetrate the plates. [RECOMMENDED]

A constant voltage "automatic" charger applies regulated voltage at approximately 13.8 to 16 volts based on the manufacturer's recommendations and temperature. A 10 amp automatic charger will cost between $30 and $60
at an auto parts store. Some sulfated batteries, depending on the size and degree of sulfation, can be recovered by applying one or two amps for 48 to 120 hours.

[An excellent automatic constant voltage battery charger is a 15 volt regulated power supply adjusted to the manufacturer's recommendations or, if not available, to voltages below with the electrolyte at 70 degrees:

Battery Type Charging Float Equalizing

Wet Low Maintenance 14.4 13.2 15.1

Wet Maintenance Free 14.8 13.6 15.5

AGM 14.6 13.8 N/A

Gel Cell 14.0 13.5 N/A

Wet Deep Cycle 15.0 13.2 15.8

To compensate for electrolyte temperature, adjust the charging voltage .0028 (2.8 millivolts) to .0033 (3.3 millivolts) volts/cell/degree. For example, if 30 degrees, then INCREASE the charging voltage to 15.19 volts for a wet low maintenance battery. If 100 degree, then DECREASE the charging voltage to 13.81 volts.]

If left unattended, a cheap, unregulated trickle battery charger can overcharge your battery because they can "boil off" the electrolyte. Do NOT use fast, high rate, or boost chargers on any battery that is sulfated or deeply discharged. The electrolyte should NEVER bubble violently while recharging because high currents only create heat and excess explosive gasses.


7.1. Recharging slowly and keeping your battery well maintained are the best ways to extend the life of your battery.

7.2. Recharging every two months will prevent lead sulfation.

7.3. In the 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 battery that is not fully charged--just distilled water and do not overfill. The plates must be covered at all times.

7.4. High ambient temperatures (above 80 degrees) will shorten battery life because it increases positive grid corrosion.

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 80% DoD and 20% DoD will five times longer than 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% and greater than 80%.

7.6. Recharge a deep cycle battery as soon as possible after each use.

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 preventative maintenance required for a deep cycle battery.


8.1. Loss of electrolyte due to heat or overcharging,

8.2. Lead sulfation in storage,

8.3. Undercharging with voltages less than 13.8 volts,

8.4. Old age (positive plate shedding),

8.5. Excessive vibration,

8.6. Freezing or high temperatures,

8.7. Using tap water causing calcium sulfation,

8.8. Corrosion.


Batteries naturally self-discharge 1% to 15% per month while in storage and lead sulfation will occur over time. If left in a vehicle, disconnect the negative cable to reduce the level of discharge. Cold will slow the 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 the batteries.

9.2. Fully recharge the batteries.

9.2. Check the electrolyte levels and add distilled water as required, but avoid overfilling.

9.4. Store them in a cool dry place, but not below 32 degrees.

9.5. Depending on the ambient temperature and self-discharge rate, periodically test the state-of-charge using the procedure in Section 4. When it is 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 using, based on the manufacturer's recommendations or 13.02 to 13.8 volts for wet batteries
and 13.38 to 14.1 volts for VRLA batteries, compensated for temperature. An automatic or smart charger will prevent you from overcharging the batteries.

9.6 Equalize only wet or flooded batteries when you remove the batteries from storage using the procedure in Section 6.


10.1. Storing a battery on a concrete floor will discharge them.

Modern lead acid battery cases are better sealed, so external leakage causing discharge is no longer a problem. [Temperature stratification within very large batteries could accelerate the internal "leakage" or self
discharge if the battery is sitting on an extremely cold floor in a warm room or installed in a submarine.]

10.2. Driving a car will fully recharge a battery.

There are a number of factors affecting charging system's ability to charge a battery. The greatest factors are how much current from the alternator is diverted to the battery to charge it, how long the current is available and temperature. Generally, running the engine at idle
or short "stop-and go trips" during bad or hot weather at night will not recharge a battery.

10.3. A battery will not explode.

While spark retarding vent caps help, recharging a battery produces hydrogen and oxygen gasses and explosions can occur. They can also occur when the electrolyte level is below the top of the plates. If a spark or flame occurs, an explosion can occur. When this happens, thoroughly rinse the engine compartment with water, then wash with a solution of one pound baking soda to one gallon of water to neutralize the residual battery acid. Then thoroughly rewash the engine compartment with water. Periodic preventive maintenance and working on batteries in well ventilated areas can reduce the possibility of battery explosions.

10.4. A battery will not lose its charge sitting in storage.

A battery has 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. (Please see Section 9.)

10.5. Wet maintenance free batteries never require water.

In hot climates, the water is "vaporized" or "boiled off" due to the high underhood temperatures. 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.

10.7. Pulse chargers, aspirins or additives will revive sulfated batteries.

Using pulse chargers or additives is a very controversial subject. Most battery experts agree that there is no conclusive proof that more expensive pulse charges
work any better than constant voltage chargers to remove sulfation. They also agree that there is no evidence that additives or aspirins provide any long term benefits.


Discharging, like charging, depends on a number of factors. The important ones are the initial state-of-charge, depth-of-discharge, age, capacity of the battery, load and temperature. For a fully charged battery at 70 degrees, the ampere hour rating divided by the load in amps will provide the estimated life of that cycle. For example, a 72 ampere hour battery with a 10 amp load should last approximately 7.2 hours.

Jack Canavera
AIR #56
'04 Classic 30' S.O.,'03 GMC Savana 2500,'14 Honda CTX 700
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Old 05-26-2004, 04:11 PM   #17
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2002 19' Bambi
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Charger with built in desulfation

Found this charger doing a quick search. Not necessarily a recommendation as much as an example.

The unit with desulfation is about midway down ($99). THere may be less expensive units available with desulfation, but typically this feature is seen only on better chargers. Considering that you can buy a 60amp IntelliPower with ChargeWizard for about $250, is really a pretty good deal. But if you like to remove your batteries during extended storage, this standalone charger would be a good investment.

BTW, GREAT writeup by RoadKingMoe. If you take the time to read his post, you will learn a LOT about batteries (maybe more than you wanted to know) and you might just be able to get longer and better performance out of your A/S 12V system.

david & bret
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Old 05-27-2004, 08:22 AM   #18
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Looks like I am going to go the golf cart 6v route.
With the Safari I have a over under set up behind my propane tanks. Works fine until you want to check the water or clean terminals. About every three months I disassemble the whole thing, clean, fill the water which has been minimal, use dialatic grease on conections and put it back together.
I looks like 6 volts will fit length wise side by side. I figure on using aluminim angle iron bolted to the existing frame. If I can find a 6 volt plasic case(2)that will fit I will use a 1 inch piece of aluminum to strap to hold it down like I do now. If the plastic boat type boxes are to big than I will build a aluminum angle iron box and cover it with aluminum using rivits, maybe a flip up door with the base bolted to the original welded frame.
Anyone have a brand of 6 volt to go with, I was going to try to stick with the interstate brand.

2001 Safari 27 rear queen
awnings all around & 150w solar
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Old 05-27-2004, 02:01 PM   #19
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I "fully" charged my 18 mo old battery and had it tested on two tester machines today, and it failed both. I bought a new battery which I will charge up overnight. Tomorrow we are taking the trailer for the long weekend to the north shore of Lake Superior.

For short storage periods I need to locate a cutoff switch at the battery to remove all parasitic loads. For longer storage periods (say a month or more) I will remove the battery and keep it charged at home.
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Old 05-27-2004, 02:20 PM   #20
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You might want to check for the draw on that battery when the disconnect switch is thrown. I know I stored my '01 Safari for as much as 45 days on its single battery and still had enough power to operate the power jack and get the trailer hitched up.

Pulling the battery out probably may not be necessary for periods up to 60 days. As noted earlier we found the draw to be .09 of an amp. which technically should not kill the battery supplied by A/S in that time period.

However at storage time, state of the battery will have an effect on how long you can go before its considered dead. I normally arrive home, and plug into 110 for a minimum of 24 hours before I move the trailer to its storage location, awaiting our next trip. That way I'm delivering it with as full a charge as possible.

Jack Canavera
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Old 06-01-2004, 01:58 PM   #21
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I'm thinking about using a Power Pulse (#735x012) to do my sulfation phase on my battery. It works with my existing charger.

Any thoughts?

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Old 06-01-2004, 09:04 PM   #22
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The PowerPulse looks like a good unit and should work. The important thing is to check battery water with the type of charger you are using. I've been happy with my PulseTech Solargizer solar unit as well as the BatteryMinder I use. The only time the on-board Magnetek is charging is when I am hooked up to shore power and that is not much since most of my camping is boondocking.

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Old 06-02-2004, 07:03 AM   #23
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Based on the description of the PowerPulse webpage, I would say that this will work. Understand that when boondocking, it is using energy FROM the battery to run a DC-to-DC converter, so in effect, it is draining the battery. The webpage did not give the power requirements, but it states that it "uses a small portion of the battery's own energy so it is working 24-hours a day. Overtime, even small parasitic loads can discharge a battery and as there is no real reason to desulfate on a continual basis, I would install a heavy duty, DPDT switch so that you can remove one leg of BOTH the input and output wires on the unit. This way, you can ensure that there are NO parasitic loading effects from either side of the unit. About once a month, you would need to switch it on for several hours to desulfate the battery. You also need to ALWAYS check battery water levels before starting a desulfation cycle. If the plates are covered don't add water (distilled) until after the cycle (to allow expansion due to heating during the desulfation). After the desulfation, you can top off the battery with more water.

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Old 06-02-2004, 03:08 PM   #24
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Good suggestion about the DPDT switch. We Boondock alot and I am very mindful of parasitic loads. I will check on it's draw and probably install a switch anyway. I also carry my Honda EU-3000is to recharge. Since the new CCD monitor panel measures battery voltage, I always recharge at 12.2 VDC (50% State of Charge). Thanks!


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