I have fixed many devices with a new ebay $5.00 battery, and take apart device and use a heat gun to dry it out. Or take it apart and put in bag of silica gel or uncooked rice for a few days.
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"Look, let me explain something to you. I'm not Mr. Lebowski. I'm the Dude. So that's what you call me. That, or His Dudeness … Duder … or El Duderino, if, you know, you're not into the whole brevity thing."