By comparison, Gel-filled VRLA has a higher internal resistance, which makes it less suitable for high-rate discharging common with UPS applications. It does offer advantages in terms of a wider operating temperature range (-40°C to +55°C) and extended design life.

This guide explains the different lithium-ion battery types. LiCoO2 and lithium polymer are appropriate for consumer electronics and have safety issues. However, LiFePO4 is the safe and reliable choice for a UPS since it is a very stable chemistry.

So to begin with, a nice easy way to check the health of your battery is looking at the state of charge indicator. This provides a snapshot of your battery's current condition. Green means it is charged and healthy, clear means it needs to be recharged, and red means it needs replacement.

Dry-cell UPS batteries can be a good choice if you're looking for something small enough to fit in tight spaces with little weight. Longer Storage: Dry-cell batteries are typically used as primary cells and therefore can handle long periods of storage.