Energizer de-energizes lithium batteries
New Energizer Advanced Lithium batteries are a less powerful, but cheaper, version of its Energizer Ultimate power cells.
Disposable lithium batteries--a market seemingly cornered by Energizer's Ultimate Lithium batteries--are great if you need enduring power. They're not great for the environment and they're too slow to use in a camera flash, but they last much longer than alkalines and significantly longer than rechargeables. At $3 apiece (based on the street price of a 4 pack), they're also someone sticker shocking. So we shouldn't be surprised that Energizer has decided to sell the Energizer Advanced Lithium version with a kindler, gentler price of about $2 each.
The company only cites the performance of the Advanced batteries to that of alkalines (Energizer Max)--claiming 4x the life in a digital camera compared with 8x for the Ultimates. So unless you can find the Advanced cells for less than half the price of the Ultimates, the Ultimates should remain the better buy on a per-shot basis.