Charging battery...
- Thread starter JKL
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Re: Charging battery...
It's best to never discharge batteries in general. The total amount of charge/discharge coulombs is one of the parameters determining battery live. In order to get the chemical composition of nicads restored (the so called memory effect...but this has nothing to do with "memory") it's sometimes needed to discharge/recharge a couple of times , but never dicharge below 3/4 of the initial voltage. Top-off charging batteries when they are stored for a longer time avoids unbalance.
It's best to never discharge batteries in general. The total amount of charge/discharge coulombs is one of the parameters determining battery live. In order to get the chemical composition of nicads restored (the so called memory effect...but this has nothing to do with "memory") it's sometimes needed to discharge/recharge a couple of times , but never dicharge below 3/4 of the initial voltage. Top-off charging batteries when they are stored for a longer time avoids unbalance.
Scottdvx100
Veteran
Re: Charging battery...
Most chargers these days are smart enough not to over charge however it's probably a good idea not to leave the battery constantly on the charger once it has charged.
Most chargers these days are smart enough not to over charge however it's probably a good idea not to leave the battery constantly on the charger once it has charged.
Re: Charging battery...
Li-ion end of charge voltages are very critical. A few tens of millivolts on a 2 cel bat (7.2 volt) can ruin the bat if it is being left for one night a couple of times. The same amount of undervoltage can easely end up in 10% less battery capacity after charging. If you are not shure about yr charger don't keep yr bat for any time longer than one hour after "full"
Li-ion end of charge voltages are very critical. A few tens of millivolts on a 2 cel bat (7.2 volt) can ruin the bat if it is being left for one night a couple of times. The same amount of undervoltage can easely end up in 10% less battery capacity after charging. If you are not shure about yr charger don't keep yr bat for any time longer than one hour after "full"
Slapdragon
Well-known member
Re: Charging battery...
Battery Care for Dummies, By Steve Jackson (who is not a Mod, but a rocker)
Batteries come in many shapes, sizes, forms, and chemical compositions. Any discussion of batteries, your mileage may vary if you are using different batteries.
All batteries are divided into two categories, "wet" and "dry". This basically means is water part of the chemical reaction for electrical generation. All professional camcorder batteries are essentially "dry."
All batteries are divided into two more categories: rechargeable and disposable. Rechargeable batteries use a chemical reaction that can be safely "reversed" by feeding electricity back through the terminals of the battery. Disposable batteries cannot safely do this (although many formulations can be recharged, the process usually generates enough heat to make it unsafe. )
There are many battery chemical formulations. In fact, even formulations that are called the same thing ("Li-Lon") may vary in composition from manufacturer to manufacturer.
Batteries used in a production environment, which include camcorder batteries (the subject of this faq) are further divided into two categories: those with memory and those without. Today, most camcorder batteries do not have "memory." Still, check the battery package and make sure. Although rare, it is possible for a batteries of different formulations to have the same "form factor" and thus require different care.
Batteries with memory require different treatment then those without. A battery with memory can become "stuck" at various charge levels if recharged without discharging. These batteries usually require that they be discharged completely before recharging. Modern battery chargers designed for batteries with memory in fact discharge the battery first, then recharge it. Still, it is a good idea to run a battery dry before you recharge.
The most common batteries used in production does not have memory. It follows the care rules listed below.
Form Factor: A batteries form factor is how much voltage it generates, and how its terminals are designed to attach to a camera. Batteries of one form factor cannot be used (generally) in cameras designed for another form factor. Common form factors found across many makes of camera are the Anton-Bauer and the Sony NP-1 form factors. Otherwise, most camera manufacturers not only have their own form factors, but changes these factors from model to model in order to drive battery sales. Inside of a form factor, there can be batteries with different features and capacities, so we would say that a particular battery is from the "family" of Anton-Bauer Gold Mounts, and understand that most or all of these batteries will function on most or all cameras designed to accept them.
Never use a battery from one family on a camera designed for another battery, even if it seems like it can be forced to fit, unless the manufacturer specifically lists compatibility. While sometimes this is obvious (a Gold Mount battery on a DVX100 without adaptor) sometimes the form factors look close enough that they can be shoe horned into functioning (especially the current trend to external "little chunky" batteries such as used by the DVX100 and the PD170). Most manufacturers will include a chart of what camcorders can accept which forms.
Batteries should be stored in a cool place, away from light, in a dry location. Heat, sunlight, and moisture can alter the chemicals in a battery, increase the aging process of the battery, or corrode the terminals of a battery.
Batteries generally withstand cold well, but often do not perform well in very cold weather. Because a battery is made of plastic surrounding a chemical compound, it expands and contracts at different rates. If you live in very cold weather, and camcorder batteries are exposed to this weather for a long time, then are brought into a warm room, they can crack, and the chemical compounds in the battery can age. If possibly, gradual changes in temperature are best for batteries.
A battery changing temperature can have moisture build up on terminals and metal surfaces. This can be solved my wrapping it in a towel or keeping it in a portabrace (which wicks moisture) until needed.
A battery with its case damaged can get water inside during temperature changes. Since the acid in batteries is dangerous to equipment and yourself, discard these batteries.
Camcorder batteries all have "protected terminals" meaning that it is difficult to cross the terminals and create an "open circuit", or to cross the terminals and then ground that cross, resulting in a ground fault. Still, it does happen. The primary culprit is the paper clip. Never carry paperclips and batteries in the same container.
Battery elements can be damaged if dropped, ruining the battery. If you drop a battery on a hard surface, set it aside on a nonflammable surface for a couple of hours to check for leakage. Then place it on a grounded charger. Do not use it in an expensive camcorder until you know it is functional and safe. Better yet, don't drop your batteries. If there are any visible dings, dents, or bulges, the battery is done, even if it looks like it may work. (A new battery is cheaper than a new eyeball if it spills acid and cheaper than a new camera if it blows the camera up).
Modern LiLon batteries have a gradual diminishment of charge capacity. Each time they are charged, they are slightly less able to charge up to the same capacity, and will last less time. If you have a large number of batteries, it may be a good idea to track charge cycles and rotate batteries to assure all age at the same rate.
Time on a shelf also reduces battery charging capacity. Older batteries, despite holding less charge, should remain in "play" despite the tendency to want to use the newer, stronger batteries.
While it is probably safe to discharge a battery all the way down when it is new, it is not good battery care. It is best to change batteries at the 25% power mark and not use the battery until recharged, unless you need the power desperately.
Keeping a battery on a charger is no longer dangerous. Modern chargers quite pushing power in when the battery is full. In fact, since the terminals are protected and the charger is usually hooked into surge protection, it is probably safer on the charger than anywhere else.
However, cheap or quick chargers are not suitable for this. Over charging can damage a battery.
Battery Care for Dummies, By Steve Jackson (who is not a Mod, but a rocker)
Batteries come in many shapes, sizes, forms, and chemical compositions. Any discussion of batteries, your mileage may vary if you are using different batteries.
All batteries are divided into two categories, "wet" and "dry". This basically means is water part of the chemical reaction for electrical generation. All professional camcorder batteries are essentially "dry."
All batteries are divided into two more categories: rechargeable and disposable. Rechargeable batteries use a chemical reaction that can be safely "reversed" by feeding electricity back through the terminals of the battery. Disposable batteries cannot safely do this (although many formulations can be recharged, the process usually generates enough heat to make it unsafe. )
There are many battery chemical formulations. In fact, even formulations that are called the same thing ("Li-Lon") may vary in composition from manufacturer to manufacturer.
Batteries used in a production environment, which include camcorder batteries (the subject of this faq) are further divided into two categories: those with memory and those without. Today, most camcorder batteries do not have "memory." Still, check the battery package and make sure. Although rare, it is possible for a batteries of different formulations to have the same "form factor" and thus require different care.
Batteries with memory require different treatment then those without. A battery with memory can become "stuck" at various charge levels if recharged without discharging. These batteries usually require that they be discharged completely before recharging. Modern battery chargers designed for batteries with memory in fact discharge the battery first, then recharge it. Still, it is a good idea to run a battery dry before you recharge.
The most common batteries used in production does not have memory. It follows the care rules listed below.
Form Factor: A batteries form factor is how much voltage it generates, and how its terminals are designed to attach to a camera. Batteries of one form factor cannot be used (generally) in cameras designed for another form factor. Common form factors found across many makes of camera are the Anton-Bauer and the Sony NP-1 form factors. Otherwise, most camera manufacturers not only have their own form factors, but changes these factors from model to model in order to drive battery sales. Inside of a form factor, there can be batteries with different features and capacities, so we would say that a particular battery is from the "family" of Anton-Bauer Gold Mounts, and understand that most or all of these batteries will function on most or all cameras designed to accept them.
Never use a battery from one family on a camera designed for another battery, even if it seems like it can be forced to fit, unless the manufacturer specifically lists compatibility. While sometimes this is obvious (a Gold Mount battery on a DVX100 without adaptor) sometimes the form factors look close enough that they can be shoe horned into functioning (especially the current trend to external "little chunky" batteries such as used by the DVX100 and the PD170). Most manufacturers will include a chart of what camcorders can accept which forms.
Batteries should be stored in a cool place, away from light, in a dry location. Heat, sunlight, and moisture can alter the chemicals in a battery, increase the aging process of the battery, or corrode the terminals of a battery.
Batteries generally withstand cold well, but often do not perform well in very cold weather. Because a battery is made of plastic surrounding a chemical compound, it expands and contracts at different rates. If you live in very cold weather, and camcorder batteries are exposed to this weather for a long time, then are brought into a warm room, they can crack, and the chemical compounds in the battery can age. If possibly, gradual changes in temperature are best for batteries.
A battery changing temperature can have moisture build up on terminals and metal surfaces. This can be solved my wrapping it in a towel or keeping it in a portabrace (which wicks moisture) until needed.
A battery with its case damaged can get water inside during temperature changes. Since the acid in batteries is dangerous to equipment and yourself, discard these batteries.
Camcorder batteries all have "protected terminals" meaning that it is difficult to cross the terminals and create an "open circuit", or to cross the terminals and then ground that cross, resulting in a ground fault. Still, it does happen. The primary culprit is the paper clip. Never carry paperclips and batteries in the same container.
Battery elements can be damaged if dropped, ruining the battery. If you drop a battery on a hard surface, set it aside on a nonflammable surface for a couple of hours to check for leakage. Then place it on a grounded charger. Do not use it in an expensive camcorder until you know it is functional and safe. Better yet, don't drop your batteries. If there are any visible dings, dents, or bulges, the battery is done, even if it looks like it may work. (A new battery is cheaper than a new eyeball if it spills acid and cheaper than a new camera if it blows the camera up).
Modern LiLon batteries have a gradual diminishment of charge capacity. Each time they are charged, they are slightly less able to charge up to the same capacity, and will last less time. If you have a large number of batteries, it may be a good idea to track charge cycles and rotate batteries to assure all age at the same rate.
Time on a shelf also reduces battery charging capacity. Older batteries, despite holding less charge, should remain in "play" despite the tendency to want to use the newer, stronger batteries.
While it is probably safe to discharge a battery all the way down when it is new, it is not good battery care. It is best to change batteries at the 25% power mark and not use the battery until recharged, unless you need the power desperately.
Keeping a battery on a charger is no longer dangerous. Modern chargers quite pushing power in when the battery is full. In fact, since the terminals are protected and the charger is usually hooked into surge protection, it is probably safer on the charger than anywhere else.
However, cheap or quick chargers are not suitable for this. Over charging can damage a battery.
Re: Charging battery...
Interesting overview. the only thingh what is wrong is that (Nicad)batteries need to "fully" discharged. Never do this... Modern Nicad chargers partly discharge in order to avoid the voltage depression problem, incorrectly called the "memory effect"
Interesting overview. the only thingh what is wrong is that (Nicad)batteries need to "fully" discharged. Never do this... Modern Nicad chargers partly discharge in order to avoid the voltage depression problem, incorrectly called the "memory effect"
Barry_Green
Moderator
Re: Charging battery...
Definitely. The zoom motor is one of the biggest battery hogs. If you use manual zoom, your battery will last longer.
Definitely. The zoom motor is one of the biggest battery hogs. If you use manual zoom, your battery will last longer.
adolgin
DVXuser Sponsor
Re: Charging battery...
[quote author=JKL link=board=Events;num=1088669227;start=0#13 date=07/03/04 at 01:57:55]Now that we talk batteries, if using manual zoom instead of servo zoom, will the battery last longer when shooting?[/quote]
Just to satisfy your curiosity and ours, we connected a meter in line with the 7.2V line cord in our lab. The camera uses .83A when on pause. Zooming with the rocker made it go up to .9A (less than a 10% increase) while actually zooming - at the stop it goes back to .83. Recording on tape was .94A. Zooming was 1A. Opening the LCD screen changed it to 1.09A/1.15A.
This was done using the DVC80. DVX100 will be probably similar.
On the subject of the Li-Ion battery charging, every Li-Ion charging circuit we have ever seen terminates charge when the cell voltage reaches 4.1V or 4.2V depending on the design. This makes 8.2V/8.4V per pack - there are 2 cells in it. It never goes into top off charge after that, so from this point on, there is no difference if it is removed or not. The only factor to consider, if the charger stays warm, removing the battery is better, as its lifetime is affected by heat.
HTH
Alex
[quote author=JKL link=board=Events;num=1088669227;start=0#13 date=07/03/04 at 01:57:55]Now that we talk batteries, if using manual zoom instead of servo zoom, will the battery last longer when shooting?[/quote]
Just to satisfy your curiosity and ours, we connected a meter in line with the 7.2V line cord in our lab. The camera uses .83A when on pause. Zooming with the rocker made it go up to .9A (less than a 10% increase) while actually zooming - at the stop it goes back to .83. Recording on tape was .94A. Zooming was 1A. Opening the LCD screen changed it to 1.09A/1.15A.
This was done using the DVC80. DVX100 will be probably similar.
On the subject of the Li-Ion battery charging, every Li-Ion charging circuit we have ever seen terminates charge when the cell voltage reaches 4.1V or 4.2V depending on the design. This makes 8.2V/8.4V per pack - there are 2 cells in it. It never goes into top off charge after that, so from this point on, there is no difference if it is removed or not. The only factor to consider, if the charger stays warm, removing the battery is better, as its lifetime is affected by heat.
HTH
Alex
Re: Charging battery...
Agree adolgen the end of charge voltage of a Li-ion battery is (between very narrow tolerences and indeed depending on some design parameters) about 4.25 V/cell. The working voltage of a Li-ion (and also the way they are characterized) is 3.6V/cel. Just like lead acid bats have 2.1V cel voltage and the end of charge voltage is about 2.45V/cell. I don't think I mentioned the "end of charge voltages". I only mentioned the cells with their characteristic voltages by which they are known: 3.6V..7.2V... And because the end of charge voltages are design (brand) dependent and critical, and because so many people don't use original chargers I don't advise to keep batteries on all the time.
Agree adolgen the end of charge voltage of a Li-ion battery is (between very narrow tolerences and indeed depending on some design parameters) about 4.25 V/cell. The working voltage of a Li-ion (and also the way they are characterized) is 3.6V/cel. Just like lead acid bats have 2.1V cel voltage and the end of charge voltage is about 2.45V/cell. I don't think I mentioned the "end of charge voltages". I only mentioned the cells with their characteristic voltages by which they are known: 3.6V..7.2V... And because the end of charge voltages are design (brand) dependent and critical, and because so many people don't use original chargers I don't advise to keep batteries on all the time.
Re: Charging battery...
That's correct, even for Nicads and NiMH bats. The so called memory effect does not at all relate to recharging partly empty batteries. This was a myth until several years ago the real causes for voltage drop effects ("memory effects") were known.
That's correct, even for Nicads and NiMH bats. The so called memory effect does not at all relate to recharging partly empty batteries. This was a myth until several years ago the real causes for voltage drop effects ("memory effects") were known.
adolgin
DVXuser Sponsor
Re: Charging battery...
[quote author=andre link=board=Events;num=1088669227;start=15#16 date=07/03/04 at 12:12:51] And because the end of charge voltages are design (brand) dependent and critical, and because so many people don't use original chargers I don't advise to keep batteries on all the time. [/quote]
Andre, you obviously are involved in the technology aspect of the Li-Ion batteries, and most of your points are well taken. It is true, that depending on the vendor recommendations, the termination point should be what the cell is designed for - 4.1V or 4.2V. Charging up to 4.2V on a generic charger would shorten the life of a 4.1V cell.
But my point is, once the charge is terminated, it does not matter if the charger was right or wrong, there is no current going in the cell any more, so it can stay on the charger, no problem.
Alex
[quote author=andre link=board=Events;num=1088669227;start=15#16 date=07/03/04 at 12:12:51] And because the end of charge voltages are design (brand) dependent and critical, and because so many people don't use original chargers I don't advise to keep batteries on all the time. [/quote]
Andre, you obviously are involved in the technology aspect of the Li-Ion batteries, and most of your points are well taken. It is true, that depending on the vendor recommendations, the termination point should be what the cell is designed for - 4.1V or 4.2V. Charging up to 4.2V on a generic charger would shorten the life of a 4.1V cell.
But my point is, once the charge is terminated, it does not matter if the charger was right or wrong, there is no current going in the cell any more, so it can stay on the charger, no problem.
Alex