If you´re deciding whether it´s worth to use a backup battery, we bring you a few remarks why to go for it or not.
Lithium battery Xeno Energy with a lifetime of over 10 years and rules for their usage were brought to you in our article „10 years of operation for 1 battery?”. They´re usable as a “main” power source for low power consumption devices and the second main field of their usage is a power supply backup. In contrast to the smallest cells used for PC memories backup (BIOS) for example, the types, which we keep in stock feature capacity of several Ah and they´re also able to provide a relatively decent current. That enables to use such battery also for a real operation of the device (MCU) during the power supply dropout.
Probably the main reason why not to use a backup battery is a doubt about higher production costs of a given device. However, when we look at the sales price in our e-shop, we find, that common PCB types like for example XL-050F AX (LS14250CNA) ou XL-060F AX (LS14500CNA) are available for the price of max. 4 Eur/pce. At the same time, using this type of batteries eliminates the need for a battery holder, charging chip, etc.
For more detail: Backup battery soldered directly to a PCB?
French 
English