Lithium iron (the 1.5v) and other primary lithium cells (the 3v) are very important and most definitely a real battery, not just marketing. Stable voltage outpu

Lithium iron (the 1.5v) and other primary lithium cells (the 3v) are very important and most definitely a real battery, not just marketing. Stable voltage output over ther life (alkalines life is rated to 0.8 v), high capacity, wider temperature range (doen to -40), high peak current, and great shelf life.