wrote:
I am shopping for a new digital camera that would cost under $150.
My question, is the battery usage of all digital camera the same, or
do some cameras need battery replacement less frequently than others?

Usually the reviews will mention the battery life. It does vary pretty
widely, but realistically, 300 shots per recharge is not all that much
of a disadvantage over 500 shots per recharge, and I wouldn't make that
much of factor in deciding which camera to buy.

As to the type of battery, for sub-compact cameras, you have no choice,
all of them use Li-Ion battery packs because of the energy density. For
compact cameras, some of the lower-priced ones use AA batteries, while
the higher-level ones usually use Li-Ion. For digital SLRs, almost all
of them use Li-Ion batteries because of several important advantages.

You can look at "http://batterydata.com" for details on the trade-offs
of NiMH (AA) versus proprietary Li-Ion packs. There are advantages and
disadvantages for each.