Problem with my Dell Inspiron 1501

i have a probleme with my laptop. it shuts down by itmself. and haves anomalyes with the recognazations. is it the bios ? should i upgrade his bios?

i took it to a service, but they don't know what the probleme should be, they've changed some components to see if they work properly...but nothing.

if someone knows pls help me

i've heared that it's reasky to upgrade it

also, when it starts... it shows me that it doesn't recognize the battery...:| but if i press Esc it starts normaly...if i don't, his making the diagnostic control and shuts down