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Charge MacBook Battery directly from the AC adapter?

After a short heating issues, my computer has had some issues with the SMC. It won't turn on only on batteries. But if it's is charged, then I can power on the computer and it will keep turned on even if I remove the battery. The problem is that the battery died and I no longer can do that.

Then, since it can't charge the battery, is there a way I can charge the battery directly from the AC adapter? Which battery pins would I need to plug both AC adapter's positive and negative to?

Thanks for any help.

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Rafael Jung. AC does not have a positive and negative pole in the conventional sense. Are you talking about the DC site of your AC adapter?



Please don't try this! Very dangerous!

First you can't use AC to power the battery directly. The voltage is way too high and not DC to charge the battery. Even then you need some means to regulate the charge otherwise you can over charge the batteries.

Sounds like your MacBook needs service.


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Your MacBook battery is a Smart Battery. It contains a RISC micro and associated firmware. (For info on Smart Battery google 'charlie miller smart battery' and download the white paper. Your Mac and your charger (through the middle pin on the magsafe connector) both 'talk' to your batteries controller. If your battery firmware thinks something is wrong with the cells it will not allow charging. Don't try to bypass this protection, it is there to protect against fire and such. See my lengthy answer in 'Battery not charging or seen by OS'.

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