Chosen Solution
when the charge become less than 50% my Phone screen stop Suddenly and dosent work. then i remove the battry and i will retern and when i turn the phone i find 0 % in the charge.
Sounds like the battery is faulty and not holding its charge, I’d start be replacing the battery - you shouldn’t really need a guide to do this.
Your battery may be bad and needs to be replaced. Samsung Galaxy S II Teardown Use that guide up to step 2 on how to remove the battery. https://www.amazon.com/Samsung-1800mAh-E… ^There is the amazon link for a new battery.
