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Thread: Why don't they make rechargeable lithium AA/AAA batteries?

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    Default Why don't they make rechargeable lithium AA/AAA batteries?

    As the title states, why aren't AA/AAA rechargeable lithium batteries available? They sell them in non rechargeable so why not rechargeable? I've searched all over the net for an answer and haven't found anything. Isn't this the next logical step above NiMH rechargeables? Thanks for the info.

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    Flashaholic* Blindasabat's Avatar
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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    They do sell them, they are just rare. There is some liability to Li-Ion and even more making them fit where a regular consumer AA fits, since they are much higher voltage. They will destroy most products made to use 1.5V AA's since they run 3.7V to 4.2V fresh off charger. Explosion and fire is a real danger.
    Look at AW's Battery sales thread in the Dealer's section if you have something that can take the voltage of Lithium Ion's. They are called 14500 (14mm OD, 50mm long).

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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    The only rechargeable lithium technology is lithium-ion, which inherently runs at 3.7 or so volts output. There is no rechargeable lithium battery technology that runs at the 1.5-1.9 volts output of the typical lithium AA/AAA primary batteries. So the answer as to why they haven't done it is they don't know how yet.

    I expect they're working on it and whoever gets it right first (with a high current capacity, high energy density, long latency, long lifetime, and not too afraid of overcharge/overdischarge rechargeable 1.5 to 2.0 volt AA/AAA battery) will make a fortune.

    If you're referring to AAA/AA rechargeable lithium-ions, those ARE made and available. On source is CPFer AW.

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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    I thought they have Li-Po Batteries that are also rechargable... I've been out of the RC world for too long and the last thing I made used gas.

    Li-po doesn't come in AA format but I'm just saying Li-ION isn't the only rechargable Li battery out. Correct me if I'm wrong.

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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    Hello Tebore,

    The proper name for Li-Po batteries is Li-Ion-Polymer. It is a form of the Li-Ion battery.

    Tom
    Behind every Great man there's always a woman rolling her eyes...

    Most batteries don't die - they are tortured to near death, then murdered...

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    Flashaholic* monkeyboy's Avatar
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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    How do they cut the voltage in half for non-rechargeable lithium batteries? And why can't they do the same for li-ion?

    I've seen li-ion cells rated at 3.7v and 3.0v. How do they reduce the voltage from 3.7 to 3.0V?

    I would imagine, if they made protected AAA Li-ion, the protection circuitry would take up a large proportion of the battery. What I would like to see is; double length D size li-ion batteries that could be used in 2D, 4D, 6D maglites etc. and double length AA versions as well.


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    Flashaholic*
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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    Quote Originally Posted by monkeyboy
    How do they cut the voltage in half for non-rechargeable lithium batteries? And why can't they do the same for li-ion?

    I've seen li-ion cells rated at 3.7v and 3.0v. How do they reduce the voltage from 3.7 to 3.0V?

    I would imagine, if they made protected AAA Li-ion, the protection circuitry would take up a large proportion of the battery. What I would like to see is; double length D size li-ion batteries that could be used in 2D, 4D, 6D maglites etc. and double length AA versions as well.

    I believe the non-rechargeable lithium batteries use different chemistries - which happen to have lithium in them somewhere - that yield lower voltages but can't be recharged. I think 3.0 volt lithium primaries are lithium manganese hydroxide (?) and the 1.7 volters are lithium something else.

    I believe the 3.0 V lithium ions use a circuit to push back on the natural 3.7 V li-ion ouput, yielding a net voltage of about 3.1 or 3.2. The circuit, like a resistor, will eat up some of the battery energy and produce some heat in doing this.

    The 2xD (and 2xAA) li-ion battery has been suggested before and would work. However, you need a big up front investment to create a new li-ion battery design and I'm again guessing that the investors don't quite see the market to justify such a new investment.

    There are only a few CPFers, not nearly enough to justify a new battery design. Most 2xD cell lights cost $5 or less and their owners would likely not spend the $25+ needed for such a battery, plus more for the charger. Ditto with 2xAA versions. Remember, li-ions are only good for 3 years or so whether you use them or not, so it would not replace an endless supply of D cells or AA cells.

    There's also the small but not insignificant risk of mishaps with such a large li-ion cell, even protected ones. I think a worst case explosion with one that big could take your hand off, and that creates a further liability disincentive to producing one.

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    Flashaholic* monkeyboy's Avatar
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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    Quote Originally Posted by nerdgineer
    There's also the small but not insignificant risk of mishaps with such a large li-ion cell, even protected ones. I think a worst case explosion with one that big could take your hand off, and that creates a further liability disincentive to producing one.
    Now I'm afraid to put my mobile phone in my trouser pocket.

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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    Quote Originally Posted by monkeyboy
    Now I'm afraid to put my mobile phone in my trouser pocket.
    By "that big" I meant the size of 2xD cells. Unless you have a really OLD mobile phone, the battery in it is probably no larger than a pack of matches (and carefully protected, too)...

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    Default Re: Why don't they make rechargeable lithium AA/AAA batteries?

    No one has mentioned the rechargable CR-V3 which neatly gets around the voltage problem by replacing two AAs side-by-side. Trouble is that, with only 1200mAh, the capacity is not very good and you're better off using NiMh technology anyway.

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