Dell i5 3443 battery life shorter and not charging up to 100%

i buyed dell i5 3443 just 3 days ago and it has just 2 hours battery life and doesn't charge up to 100% it charges only upto 97% .

it has a problem that when the battery life becomes 61%  it goes down to 7% in a second and shutdown the laptop........................... i have warranty but i am in mountain area in nepal please help me with it...