Gadget that charges 2x 18650 and outputs 12V

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Overclocker
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Gadget that charges 2x 18650 and outputs 12V

the gadget from intl-outdoor ML-102 is fantastic but I also need one that outputs 12V 1.5A for charging my tablet and other 12v gadgets

any pointers?

Edited by: Overclocker on 06/04/2012 - 11:43
Shadowww
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How big current you need?

If 0.5A or less, you might just use http://www.ebay.com/itm/LM2577-Boost-DC-DC-Step-up-Converter-3-34V-4-35V... this board with any number of 18650's in parallel (or 2 in series)

Overclocker
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1.5A

maybe even 1.0A will do (charge only while unit is off)

Shadowww
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For 1.0A you'll have to feed it with 2x 18650 in series (Iin should be max. 3A for that chip), also put some tiny heatsink on it :Р

Overclocker
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Shadowww wrote:

For 1.0A you'll have to feed it with 2x 18650 in series (Iin should be max. 3A for that chip), also put some tiny heatsink on it :Р

 

hmm thanks for the tip! maybe i'll just run 2 protected cells and depend on the protection circuit to cutoff

question. will the output voltage be constant as the cell voltage drops?

Shadowww
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Overclocker wrote:

question. will the output voltage be constant as the cell voltage drops?

Yep, it'll be stable down to 4V (and, at this point, protection of either cell would have kicked in already, as that's 2V per cell).
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alex21
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Which tablet you got? If its ipad doesn’t that charge off 5v?
But yeah I think transformer, iconia, etc all need 12v..