The battery on my cell phone that i’ve had for approximately 2 years lasts about 10 minutes when fully charged. My last resort is buying a new battery. What can I do to make the battery life longer? It is a lithium ion battery in a kyocera cell phone.

If i do have to buy a new battery? How much would it cost me or would it be cheaper to just buy a new phone?
Added at 9:37- Can I freeze it? Would it damage it? How long should I freeze it for?
I have the backlight at 5 sec. I even disabled the backlighting for awhile but I had to turn it back on, I couldnt see anything.
Its a prepaid cell phone… no contracts and I always have the charger plugged in


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