Battery Question !
12-30-2002, 06:05 PM
#1
Guest
Posts: n/a
Battery Question !
After I completed a winter maintance charge I hooked up the charger a day later just to double check them. For a minute or so the charger shows that it is putting out a full charge. After that minute it shows that they are fullly charged, why.
Sam
Sam
12-31-2002, 06:49 PM
#2
Toxic FORMULA
Platinum Member
That's strange
. Try the charger on a different battery like your car or truck. Maybe it's just a quirk with the charger
I don't think I'd worry about it
. Try the charger on a different battery like your car or truck. Maybe it's just a quirk with the chargerI don't think I'd worry about it
12-31-2002, 09:16 PM
#3
Guest
Posts: n/a
Batteries allow how much charging input they will allow by age, temp, state of charge etc. What you have is a battery that was charged and let sit overnight and some of the surface charge dissipated, thus allowing what you see as a short full charging rate, then a drop in amps when the surface charge is recapped. Below are the basic functions of batteries to some degree, and the best way to make them live when not in daily use. It gets way more complicated than this, but I elected to keep it simple and maybe answer your question.
Starting and other lead-acid batteries are perishable. During the discharge process, soft lead sulfate crystals are formed in the pores and on the surfaces of the positive and negative plates inside a lead-acid battery. When a battery is left in a discharged condition, is continually undercharged, or the electrolyte level is below the top of the plates, some of the soft lead sulfate re-crystallizes into hard lead sulfate. It cannot be reconverted during subsequent recharging. This creation of hard crystals is commonly called Elead sulfationE It accounts for over 80% of the deep cycle lead-acid battery failures. The longer sulfation occurs, the larger and harder the lead sulfate crystals become.
Sulfation is a result of lead-acid battery discharge while in storage, which is a consequence of parasitic load and natural self-discharge. Parasitic load is the constant electrical load present on a battery while it is installed in a vehicle even when the ignition switch is turned off. The load is from the continuous operation of appliances, such as, an emmisions computer, a clock, security system, maintenance of radio station presets, etc. While disconnecting the negative battery cable will eliminate the parasitic load, it has no affect on the other problem, the natural self-discharge of battery. Thus, sulfation can be a huge problem for lead-acid batteries not being used while in storage or sitting on a dealer's shelf, in a basement, or in a parked vehicle, especially in hot temperatures.
The best way to prevent sulfation is to keep a lead-acid battery fully charged because lead sulfate is not formed. This can be accomplished three ways. The best solution is to use a charger that is capable of delivering a continuous floatEcharge at the battery manufacturer's recommended float or maintenance voltage for a fully charged battery. 12-volt batteries, depending on the battery type, usually have fixed float voltages between 13.2 VDC and 13.6 VDC, measured at 70° F (21.1° C) with an accurate (.5% or better) digital voltmeter. Charging can best be accomplished with a microprocessor controlled three stage or four stage charger, such as a Battery Tender (Deltran), Truecharge (Statpower), BatteryMinder, Schumacher, etc., or by voltage regulated float charger set at the correct voltage, such as a ChargeTek, etc. By contrast, a cheap, unregulated trickleEcharger can overcharge a battery and destroy it.
Multiple stage charging is the best and most economical way to recharge batteries. Three stages are usually
preferred,bulk, absorption, and float.
Bulk charging is done to return 75% of the energy removed from the battery quickly. Amperage is kept as high as thebattery and charging source will allow, usually equal to a value of 10-20% of the batteries ampere-hour capacity ( a 220 ampere-hour battery would be charged at 22 to 44 amps, expressed as C10 or C5. The equation for determining thisvalue is Capacity divided by charging current determines time to charge fully [C value]
220/5=44=C5) When thebattery voltage reaches approximately 2.41 volts per cell (14.5 volts for a 12 volt battery), absorption stage isinitiated.
In absorption stage, the current into the battery is limited to hold the terminal voltage at a pre-set value just below it's gassing voltage, usually 14.5-14.6 volts, for a specified period of time, from half an hour to several hours, depending on the specifications of the battery manufacturer. During this time, the battery is allowed to slowly absorb approximately 20% of the electricity being returned in the charging process. At the end of the given time, the float stage is initiated.
Float charging is a condition in which the battery is held at a specified voltage that is well below it's gassing point, but high enough that the remaining 5% of capacity can be returned. Typical float voltage for a 12 volt lead acid battery might be 13.1 volts. A battery can be left on float charge indefinitely without damage or excessive water loss.
Then there is the issue of occasional over-charging of deep cycle batteries, which is required for good battery health. This is also called an "equalizing charge", and it is applied once a month or so to help even out the state of charge between all of the series-connected cells in a battery. The regulator or charge controller is set to allow the battery's terminal voltage to reach 15+ volts for a period of several hours. This will cause furious gas production in the cells, helping to strip away any soft sulfate deposits, and de-stratifying the electrolyte. Care must be taken to allow the pressure inside the cells to dissipate, usually by removing the cell caps. This generally leads to electrolyte being spattered onto the top of the battery, which must be cleaned up after the equalizing process. The hydrogen gas produced is highly explosive, and all care should be taken to prevent it's being ignited.
The state of charge of any lead-acid battery can be determined by the use of a battery hydrometer, which indicates the specific gravity of each cell in a battery bank. Personally, I prefer modern digital electronic instruments to screwing with corrosive acids. When the batteries are operating properly, the readouts from the instruments is more than adequate to indicate the state of charge. I save the hydrometer reading for once-or-twice a year maintenance and for locating a weak cell when performance drops off due to age.
Hope this helps, and Happy New Year!
Starting and other lead-acid batteries are perishable. During the discharge process, soft lead sulfate crystals are formed in the pores and on the surfaces of the positive and negative plates inside a lead-acid battery. When a battery is left in a discharged condition, is continually undercharged, or the electrolyte level is below the top of the plates, some of the soft lead sulfate re-crystallizes into hard lead sulfate. It cannot be reconverted during subsequent recharging. This creation of hard crystals is commonly called Elead sulfationE It accounts for over 80% of the deep cycle lead-acid battery failures. The longer sulfation occurs, the larger and harder the lead sulfate crystals become.
Sulfation is a result of lead-acid battery discharge while in storage, which is a consequence of parasitic load and natural self-discharge. Parasitic load is the constant electrical load present on a battery while it is installed in a vehicle even when the ignition switch is turned off. The load is from the continuous operation of appliances, such as, an emmisions computer, a clock, security system, maintenance of radio station presets, etc. While disconnecting the negative battery cable will eliminate the parasitic load, it has no affect on the other problem, the natural self-discharge of battery. Thus, sulfation can be a huge problem for lead-acid batteries not being used while in storage or sitting on a dealer's shelf, in a basement, or in a parked vehicle, especially in hot temperatures.
The best way to prevent sulfation is to keep a lead-acid battery fully charged because lead sulfate is not formed. This can be accomplished three ways. The best solution is to use a charger that is capable of delivering a continuous floatEcharge at the battery manufacturer's recommended float or maintenance voltage for a fully charged battery. 12-volt batteries, depending on the battery type, usually have fixed float voltages between 13.2 VDC and 13.6 VDC, measured at 70° F (21.1° C) with an accurate (.5% or better) digital voltmeter. Charging can best be accomplished with a microprocessor controlled three stage or four stage charger, such as a Battery Tender (Deltran), Truecharge (Statpower), BatteryMinder, Schumacher, etc., or by voltage regulated float charger set at the correct voltage, such as a ChargeTek, etc. By contrast, a cheap, unregulated trickleEcharger can overcharge a battery and destroy it.
Multiple stage charging is the best and most economical way to recharge batteries. Three stages are usually
preferred,bulk, absorption, and float.
Bulk charging is done to return 75% of the energy removed from the battery quickly. Amperage is kept as high as thebattery and charging source will allow, usually equal to a value of 10-20% of the batteries ampere-hour capacity ( a 220 ampere-hour battery would be charged at 22 to 44 amps, expressed as C10 or C5. The equation for determining thisvalue is Capacity divided by charging current determines time to charge fully [C value]
220/5=44=C5) When thebattery voltage reaches approximately 2.41 volts per cell (14.5 volts for a 12 volt battery), absorption stage isinitiated.
In absorption stage, the current into the battery is limited to hold the terminal voltage at a pre-set value just below it's gassing voltage, usually 14.5-14.6 volts, for a specified period of time, from half an hour to several hours, depending on the specifications of the battery manufacturer. During this time, the battery is allowed to slowly absorb approximately 20% of the electricity being returned in the charging process. At the end of the given time, the float stage is initiated.
Float charging is a condition in which the battery is held at a specified voltage that is well below it's gassing point, but high enough that the remaining 5% of capacity can be returned. Typical float voltage for a 12 volt lead acid battery might be 13.1 volts. A battery can be left on float charge indefinitely without damage or excessive water loss.
Then there is the issue of occasional over-charging of deep cycle batteries, which is required for good battery health. This is also called an "equalizing charge", and it is applied once a month or so to help even out the state of charge between all of the series-connected cells in a battery. The regulator or charge controller is set to allow the battery's terminal voltage to reach 15+ volts for a period of several hours. This will cause furious gas production in the cells, helping to strip away any soft sulfate deposits, and de-stratifying the electrolyte. Care must be taken to allow the pressure inside the cells to dissipate, usually by removing the cell caps. This generally leads to electrolyte being spattered onto the top of the battery, which must be cleaned up after the equalizing process. The hydrogen gas produced is highly explosive, and all care should be taken to prevent it's being ignited.
The state of charge of any lead-acid battery can be determined by the use of a battery hydrometer, which indicates the specific gravity of each cell in a battery bank. Personally, I prefer modern digital electronic instruments to screwing with corrosive acids. When the batteries are operating properly, the readouts from the instruments is more than adequate to indicate the state of charge. I save the hydrometer reading for once-or-twice a year maintenance and for locating a weak cell when performance drops off due to age.
Hope this helps, and Happy New Year!
12-31-2002, 09:41 PM
#4
Guest
Posts: n/a
WOW ! that was a mouth full. I do thank you for the lesson, it was very informitive. I will check out a float charger as soon as I can. The only problem is I have five batteries that need tending over the winter. I really don't want to buy five systems, any thoughts.
THX
Sam
THX
Sam
