Lithium batteries are easier to charge, have a more suitable voltage, are lighter for the same energy and have no memory effect. They also have a great even voltage drop during discharge which makes for accurate charge indicators (Sony used to advertise them as "infolithium" back in the day)
Lithium batteries are pretty great except for the fire risk. And Lithium mining is bad for the environment (lots of chemical waste during extraction) so using them for single use stuff is horrible.
Lithium batteries are pretty great except for the fire risk. And Lithium mining is bad for the environment (lots of chemical waste during extraction) so using them for single use stuff is horrible.