Or - is this the easiest solution? - if I understand this board correctly, it takes in a voltage up to 8V, charges a single lithium cell (4.2V), and outputs a boosted voltage adjustable between 4.3V and 27V (so, that could be the ~7V required to run the PowerBook).
I guess that multiple cells in parallel would provide the necessary current, if this board can charge them. Otherwise, one board per cell wouldn’t be too bad to arrange.
The only flaw I can see in this is that the PowerBook would not be able to see any decrease in battery voltage, so there would be no warning of a flat battery until the boost converter simply cuts out.
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I guess that multiple cells in parallel would provide the necessary current, if this board can charge them. Otherwise, one board per cell wouldn’t be too bad to arrange.
The only flaw I can see in this is that the PowerBook would not be able to see any decrease in battery voltage, so there would be no warning of a flat battery until the boost converter simply cuts out.
3.49US $ |10pcs 3.7V 4.2V Lithium Li ion 18650 Battery Charger Board DC DC Step Up Boost Lithium Battery Charging Step Up Board Module|Integrated Circuits| - AliExpress
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