Please find Below mentioned Batteries options available for different digital cameras

Disposable AAs importance & use:

Disposable Alkaline batteries are widely used in number to items & when we purchase a digital camera mostly we get these non-rechargeable batteries within the digital camera box.
Talking about its importance, as we all know that Digital cameras are high power consumption and using AA Alkaline batteries mean throwing away almost a pair of batteries daily that is not fair.

Conclusion: We should only use alkaline batteries in emergency situations only when rechargeable batteries are not available somehow.

Rechargeable AAs (NiCd & NiMH) importance & use:

Rechargeable Lithium AAs are expensive than Alkalines, however we can recharge it later on to use it afterwards and it poses about three times the power packed in half the weight, they are ideal to carry as a backup specially when traveling.
NiMH (Nickel Metal Hydride) rechargeable AA batteries are much better than the NiCd (Nickel Cadmium) AAs. We can recharge them anytime however in NiCd batteries we could not recharge it before it fully get discharged because doing so harmed the batteries.

Conclusion: NiMH rechargeable batteries are available everywhere in every place so we need to select it as our camera battery.

Rechargeable Lithium-ion Batteries importance & use:

Li-ion (Lithium-ion) rechargeable batteries are lighter, more compact, but more expensive than NiMH batteries. They have no memory effect and always come in proprietary formats (there are no rechargeable Li-ion AAs). Some cameras also accept disposable Lithium batteries, such as 2CR5s or CR2s via an adapter, ideal for backup purposes.
Charging