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J. Bernard Vallon
03-16-2007, 02:21 PM
I've heard a lot of myths/superstisions about batteries and their life-spans.

Things like:
-you should use a battery until it is fully dead
-you should unplug a battery as soon as its fully charged
-never leave a battery charged on the shelf
-always leave a battery charged on the shelf (you see my dilemma)

These myths are often connected to the kind of battery, Li-ion, ni-cad, ni-mh, etc.

Sometimes they come from the manufacturer, sometimes not.

Id like to, of course, get the best performance out of my Red Batteries. Could someone dispel some of these myths, or confirm them? Maybe even give us electro-chemical explanations as to why some this happen?

Thanks

Manfred Lopez
03-16-2007, 02:34 PM
I heard that you should only charge batteries on sundays, because thatīs when you get the cleanest power from city lines. :biggrin:

But seriously, I also would like to know.

Jeff Kilgroe
03-16-2007, 03:23 PM
Well, ni-cad and nimh batteries had memories really bad and it was best to fully drain before recharging and recharge all the way before using. Li-ion isn't effected this way (or at least not enough to really matter). As for storing batteries, makes no difference if they're charged or not. Except going back to those with memory effects. If stored fully charged, be sure they're drained before re-charging. No need to unplug a battery once it's done charging... Provided the charger knows when it's done charging and will stop sending power to it. Old chargers back in the day, especially on consumer devices, didn't shut themselves off. Or often they would, but if you left a charged battery on the charger, the unit would sense when it wasn't fully charged and would continue to top-off the battery all the time it was connected. This was a real problem with ni-cad and ni-mh batteries due to that memory issue. No better way to ruin your ni-cad battery than to leave it connected to a charger that would continuously sense a drop in power and try to feed it more juice.

Another battery myth that tends to float around is:

- All batteries are the same, only a couple companies in the world make the cells.

This is particularly a common rumor with alkaline cells. And is often perpetuated by bargain battery salesmen as they push generic branded replacements for cell phones, security systems, laptops, etc..

I can't comment on RED batteries or most other V-Mount options. Red has good prices on their batteries compared to stuff from Sony and other big names. I'm not so sure about the charger, if it's a dual battery charger as well as a DC power supply, then it's a good price. Actually we have been told it's a DC power supply, I just haven't seen any confirmation as to it being a single or dual charger. If it's a single charger + DC, then the price is still fine, but may be a bit high. Don't get me wrong, I'm not complaining about prices. Sony sells a single charger without DC power output for about $900.

PaulClements
03-16-2007, 07:28 PM
I've been doing a bit of research into batteries as i'm actually hoping to start selling them and will have some test models soon. I'm in the process of making a guide to go up on a website should I decide to sell them and I'll be sure to let people here know about it because there are some interesting facts you need to know about storage/use/recharging that can help to give more life to your batteries. Even though I will be doing it as part of a business at the end of the day the information will be the same for RedBrick's.

The prices I will hopefully be trading at will be very competitive and suitable as a budget option or backup to red's offerings. And the price will cover free shipping and duty/tax charges worldwide within the price so the price is the same for everyone wherever you are.

There are of course differences between Li-Ion and Ni-Cd and Ni-Mh. With a Li-Ion battery it actually starts to lose it's capacity from the moment it is constructed. There are other types of batteries such li-Pol (Lithium Polymer) that do not lose their capacity but typically have slower recharge times lower capacities to begin with and are more expensive to manufacture and therefore purchase.

Last year Sony recalled a huge ammount of batteries as many know, but the cause of this was contamination in the construction of the battery and was effectively an odd occurance.

Anyway here's a short guide:


You must never short ciruit one i.e. put a wire between the + and -. Although as V-Locks this isn't something you do by accident, if you manage to do this by accident I'd be suprised and if you do it on purpose then you are a bit of a loon.


A Li-Ion battery should be protected from direct knocks and extreme temperatures. Leaving one out in the blazing sun all day isn't the most sensible idea.


Never run a Li-Ion to 0 capacity (They usually have built in measures to stop this happening anyway) But if the battery has a means of showing it is low on charge then you might as well swap it out, especially if you have another spare anyway.


Li-Ion like to be stored in a cool place, a fridge is quite a good place apparently but my advise would be to put it in a airtight sealed plastic bag before hand. DO NOT PUT IT IN A FREEZER THOUGH. This will actually freeze the electrolytes and then your batteries will be screwed.


If you are not going to be using the battery for a while and are going to store it on a shelf it is best to leave it at about 40% capacity. If you store it fully charged it's natural capacity drop will be greater.


It's a wise idea to recharge a battery (At least to 40%) rather than leave it empty (When leaving for a few days or so). If left empty for a very long period (About two years) it'll be completely knackered.


Most modern batteries and charger have built in measures to stop overcharging. But if you notice a battery is fully charged it doesn't hurt to remove it and put it away until needed. And it wouldn't be a good idea to leave the battery on charge for very long periods (Days) since this will speed up the natural capacity loss.


Don't submerge in water... duh! Using them completely exposed on a very rainy day might be a little daft... hell why would you be using your beautiful camera exposed anyway???


There are lots of things to consider but these are some of the main points. Like I said all being well I will have a more thorough description available of how to look after and get the most from your batteries soon and will post something in the near future until then I hope this is of help.

J. Bernard Vallon
03-16-2007, 07:36 PM
very helpful.

I'm considering becoming religious about your advise, particularly the 'fridge storage and the 40% rule, and see if i get considerably more life out of my redbricks.

PaulClements
03-16-2007, 08:00 PM
use one with the advise and one without and see which is better after 12 months :)

If you are actually religous and do treat them well there is no reason a battery couldn't still be useable after 4 or 5 years. That said if you do find yourself eating through the batteries give me a shout and maybe I'll be able to hook you up with a cheap alternative :)

Ralph Oshiro
03-16-2007, 08:53 PM
Never run a Li-Ion to 0 capacity (They usually have built in measures to stop this happening anyway) But if the battery has a means of showing it is low on charge then you might as well swap it out, especially if you have another spare anyway.
The Anton Bauer battery manual is what I've been going by for all battery chemistries. But I've never really known what to do with Li-ions. What is your source on the "never run Li-ion to zero?" I know that Ni-cads should NEVER be run to zero, but I've read manufacturers' instructions that tell you explicitly to store Li-ions COMPLETELY depleted (Panasonic, Nikon, etc.), and that you should NEVER store Li-ions fully charged. I used to do that, but it's a PITA, because all your batteries are never "ready to go." EDIT: I just read the Anton Bauer owner's manual for a Dionic 90, and it says to keep Li-ions charged at 50% for long-term storage.

For practical buyng advice, according to the Anton Bauer guide:

• Ni-cads have the most recharging cycles.
• Li-ions have the fewest recharging cycles.
• Ni-Mh are in the middle.

After reviewing all the facts about all the different chemistries, I found for myself, at least, that Ni-cads still gave the best bang for the buck. I ended up buying four Anton Bauer ProPak14 65Wh bricks (without the digital guage) for $375 USD each.

PaulClements
03-16-2007, 09:18 PM
Ni-Cads are good Ralph, but they don't have the weight benefits of Li-Ion's. Anton Bauer ProPak14 65Wh weigh 2.8KG or 5.4lbs. An equivilent Li-Ion battery will weigh in at about 700g or 1.5lbs, on a loaded camera it's a fair old extra bit to carry around; effectively four times the weight.

Li-Ion's don't suffer as low a self-discharge rate as Ni-Cad's nor do they suffer memory effect. Memory effect means you should run the Ni-Cad battery down completely before recharging it rather than topping up a slightly used battery, which isn't always useful.

Truth is each type of battery has it's uses on different occassions or for different people. Horses for Courses.

PaulClements
03-17-2007, 08:29 AM
...will be very competitive and suitable as a budget option or backup to red's offerings.

I guess they'll be less budget now the charger's price has been amended lol :)

Joel Kaye
03-17-2007, 09:08 AM
Nice little FAQ

http://www.greenbatteries.com/libafa.html

Jeff Kilgroe
03-17-2007, 10:36 AM
DO NOT PUT IT IN A FREEZER THOUGH. This will actually freeze the electrolytes and then your batteries will be screwed.

Not sure I agree with this one. I don't store batteries in a freezer or anything like that, but I regularly work outdoors with NiCD and Li-Ion in temps that go far below a typical freezer.

The cold does have an adverse affect on charge time and power output with most batteries, but I haven't seen any degenerative effects from the cold or anything that would suggest it could ruin your batteries. It also depends on the specific battery, how it is manufactured, exactly which compounds and electrolytes are inside it. I've got some batteries that will apparently freeze solid at about -5F and some that keep chugging along at 20 degrees colder than that.

Ralph Oshiro
03-17-2007, 03:55 PM
Ni-Cads are good Ralph, but they don't have the weight benefits of Li-Ion's. Anton Bauer ProPak14 65Wh weigh 2.8KG or 5.4lbs. An equivilent Li-Ion battery will weigh in at about 700g or 1.5lbs, on a loaded camera it's a fair old extra bit to carry around; effectively four times the weight.
Don't get me wrong, Paul. When I'm spending someone ELSE'S money, I ALWAYS insist on Anton Bauer Dionic Li-ions! Those Dionic 160s weigh NOTHING and last FOREVER! But at a $1,000 each, and perhaps 200-fewer charge cycles, for my own coin, I went with the cheap heavy-ass, old-fashioned Ni-cad bricks instead.

PaulClements
03-18-2007, 12:52 PM
Interesting Jeff, I'm only going from research I've done on it and that's what I've been advised. If I was shooting outside in such cold temperatures I would advise covering both the batteries and RedDrive anyway for added protection. I believe the very lowest Li-Ion batteries will work upto is -40C after that you're batteries are boned, so Yes perhaps storing in a freezer wouldn't be too bad, but at the end of the day I wouldn't bother because you get no more advantage than storing in a fridge and since some advise states not to freeze them it's better to er on the side of caution.

PaulClements
03-18-2007, 01:00 PM
Don't get me wrong, Paul. When I'm spending someone ELSE'S money, I ALWAYS insist on Anton Bauer Dionic Li-ions! Those Dionic 160s weigh NOTHING and last FOREVER! But at a $1,000 each, and perhaps 200-fewer charge cycles, for my own coin, I went with the cheap heavy-ass, old-fashioned Ni-cad bricks instead.

For sure Ralph, budget is something we all have to consider. The batteries I'm hoping to test in the near future are unbranded 150's both Gold mount or V-Lock and I reckon I would retail for about $280 and maybe discount multiple orders like $1000 for 4 perhaps... Whether they are any good is what I need to find out. Obviously with AB you are buying tried and tested but if they turn out to be any good then it'd certainly be a viable budget alternative/backup/supliment for many.