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Author Topic: Rechargable 1.5volts batteries not exist?  (Read 7764 times)

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fontas

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Rechargable 1.5volts batteries not exist?
« on: August 29, 2008, 01:13:25 AM »
I have a camera that is powered by 2 1.5 volts batteries. It is funny because rechargable batteries that as far as i know have the most 1.2 volts and many miliamperes.
I charge 2 of them am full, and put them in the camera. Then start the camera and always get the low battery signal. But bateries are full and brand new, double checked.

I search for 1.5 volts rechargable and guess what " THEY DO NOT EXIST "    ??? :-\

Or do they? Do you have any idea?
Thanks

kam

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fontas

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Re: Rechargable 1.5volts batteries not exist?
« Reply #2 on: September 01, 2008, 22:01:52 PM »

spic0m

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Re: Rechargable 1.5volts batteries not exist?
« Reply #3 on: September 01, 2008, 22:20:02 PM »
I want to believe that even if your camera shows "no battery" you'll still get the duration you excpect, give it a try.

spic0m

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Re: Rechargable 1.5volts batteries not exist?
« Reply #4 on: September 02, 2008, 13:05:32 PM »
Here's a better description. :)

Can NiMH batteries be substituted for alkaline batteries even though they are only 1.2 volts?

Yes, for most high drain electronic applications NiMH batteries are ideal substitutes and you needn't worry about the apparent voltage differences.  Even though alkaline batteries are rated at a nominal 1.5 volts, they only deliver 1.5 volts when they are fully charged.  As they begin to discharge the voltage of alkaline batteries continuously drops.  In fact, over the course of their discharge, alkaline batteries actually average about 1.2 volts.  That's very close to the 1.2 volts of a NiMH battery. The main difference is that an alkaline battery starts at 1.5 volts and gradually drops to less than 1.0 volts.  NiMH batteries stay at about 1.2 volts for most of their discharge cycle.

There are a couple of cases where their actual voltage difference may be important to you.  In the case of a device like a radio, where a higher voltage can mean a stronger signal, a fresh alkaline battery may be more desirable - but more expensive -  than a rechargeable NiMH battery.  This is also true for a flashlight, which will be brighter with the initial higher voltage of alkaline cells.  This minor difference may not be important to you and is probably offset by the much lower cost of operating NiMH batteries.  And keep in mind that the alkaline battery only has a higher voltage when it is fully charged.  Once it gets to 50% capacity or less, it will be delivering a lower voltage than a NiMH battery.

The one time when the voltage difference of the two is important would be in the case of a device that checks the voltage of a battery to estimate the amount of charge left on the battery.  Because the voltage of an alkaline battery drops at a very predictable rate it's possible to estimate the amount of capacity left in an alkaline battery based solely on its voltage.  (1.5 volts - fully charged, 1.25 volts - 50% charged, 1.0 volts - almost fully discharged). But a NiMH (or NiCd) battery stays at about 1.2 volts until it is nearly completely discharged.  This makes it almost impossible to know the amount of capacity left based on its voltage alone.  When a device that's using NiMH batteries indicates the battery is low, it's time to change the batteries now!


This answer found at: http://www.greenbatteries.com/nibafa.html

Mercury

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Re: Rechargable 1.5volts batteries not exist?
« Reply #5 on: September 02, 2008, 22:23:33 PM »
Actually, in some cases, alkaline bats are same price or cheaper than rechargeable. How this comes? Easy. You may get 8 pairs alks AA for 1.5 euro. Rechargeable are more expensive, about 4 euros for 4 bats. Alkalines cost 0.18 cents each, where rechargeable  1 euro each.

So, you need to recharge the batteries at least 4 times to have match price correct? WRONG.
Alkalines will last more than 2 times as a rechargeable. So you need to charge 8 times to have price match e correct? WRONG, again.

Rechargeable batteries will lose 10% of it's capacity in the first 24 hours, even without operation. From then on, they lose about 10% per month and that is not so bad, but consider that alkaline batteries will last up to 6-8 years!!! So, in some cases, alkaline are... priceless  ;D ;D ;D

And of course, do not forget that, unless you charge rechargeable with solar power or wind power, they do not charge for free. Every time that you charge a battery you use double the power that will provide (due to thermal)...

spic0m

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Re: Rechargable 1.5volts batteries not exist?
« Reply #6 on: September 02, 2008, 22:28:29 PM »
Jesus! Are you an economist?

Mercury

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Re: Rechargable 1.5volts batteries not exist?
« Reply #7 on: September 02, 2008, 22:30:58 PM »
Jesus! Are you an economist?

No i am not. These are facts

fontas

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Re: Rechargable 1.5volts batteries not exist?
« Reply #8 on: September 03, 2008, 22:39:03 PM »
I will insist that 1.2 volts will not play.
Actually, some times they do, and some times they do not. And when they work, is mainly when the weather is hot  :o :o :o
Really, belive me, it happens. When it is cold, then it does not turn on. Actualy it turn on but instantly turn off and say "low battery".

IF it work, then all ok. You always have the sign "low bat" but you can have for example more than 150 shots. Strange also but it happens.



Thanks for the economic analysis anyway  ;)

Mercury

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Re: Rechargable 1.5volts batteries not exist?
« Reply #9 on: September 10, 2008, 00:27:07 AM »
I will insist that 1.2 volts will not play.
Actually, some times they do, and some times they do not. And when they work, is mainly when the weather is hot  :o :o :o
Really, belive me, it happens. When it is cold, then it does not turn on. Actualy it turn on but instantly turn off and say "low battery".

IF it work, then all ok. You always have the sign "low bat" but you can have for example more than 150 shots. Strange also but it happens.



Thanks for the economic analysis anyway  ;)

I had a flight once and i had my camera fully charged. I load it with the baggage. On flight it might get very cold down there. When i got out of the plane, the camera was completely empty. It is new so it had no bad battery. If you forget it open it shut down itself, but also the protection for wrong turn on was active so no way to work during flight.
My friend told me it was because of the cold. This might be true...  :-\

Someone had an experience like this?

d_click

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Re: Rechargable 1.5volts batteries not exist?
« Reply #10 on: September 16, 2008, 22:06:10 PM »
I never had problem with my camera rechargeable batteries.