Replacing GBA SP battery with a modern Li-ion?

Discussion in 'GBA - Hardware, Devices and Utilities' started by dude22072, May 8, 2016.

  1. dude22072
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    dude22072 GBAtemp Regular

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    Is it possible to just replace the GBA SP's battery and wire up a standard Li-ion of the appropriate voltage? If so, 1) what are the mAh limits?, 2) will the SP's charger still work?, 3) When will the power LED turn red?
     
  2. FAST6191

    FAST6191 Techromancer

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    If you are asking about Amp hour limits like that then is probably not the project for you. It is a measure of the capacity of a battery and thus you can have as much as you can find someone willing/able to make. I would not advise going below the existing one unless you get a weight drop of some note for your effort (you won't in this case).

    The trouble will come in the differences in charging type/chemistry. Charging batteries is not just a matter of apply voltage source and get busy waiting. Various different ways will require various different things (constant voltage periods, constant current periods, temperature monitor, voltage fluctuation monitoring, simple timing....), though there are shortcuts and there are chips available that handle charge management. Naturally NiCd uses a rather different method to any of the Lithium ones really (I hope anyway, there might be some odd Lithium chemistry that does OK). You probably could bypass or rewire the onboard charge circuitry but I imagine it would be easier to take the approach I saw in various 360 wireless charge packs and stick a USB on the battery somehow and charge the battery directly.

    The LED should still change. As far as I am aware it happens when the Voltage starts to drop below a certain limit (regardless of chemistry batteries as they deplete drop in voltage when loaded). Lithium family batteries do still drop it a bit when they start to go down so it should even still work reasonably well -- how well as far as comparing how long you get from it coming on will vary with a few things but probably not massively.