Lifetime is just highlighting the length of time something is, was or will be alive. So you can use it for current things/animals etc which are alive. E.g. In my lifetime I want to visit all the countries in the world. - So here I'm still alive and just referring to what I desire to do during the time I'm alive. So mainly animals, humans and plants etc but it's mostly animals and humans they're both used with. You can use lifetime and life with things which are alive. E.g. The shark's life is very lonely. During its lifetime it will lose and grow many teeth.

Lifetime usually represent fixed interval Life has broader meaning and can mean different things based on context. lifetime can be used with "it". for example life of radioactive atom has a lifetime of xx # of years.