Broken Acer Latop REPLY PLEASE

Well i have a Acer laptop and it wont turn on anymore.
i tried almost evrything like hold powerbutton switch memory card and stuff like that.
If i dont do anything for like 3/6 months with it and i power it up 3 sec later it turns off.

Acer TravelMate
5740 Series
2 years old

First i tried Holding the powerbutton worked for 1/3 months.
Then i tried RAM switch worked for 1/3 months
Then i tried Both like 30 second button and memory switch. worked for 1/3 Months
After that i did like 30 sec button 0 RAM 30 Sec Button 1 Ram stick 30 sec Button 2 Ram Sticks

And YES The backup battery is replaced.
?is it possible that the Backu battery is wrong plaed like the - is on the + and the + is on the -?

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