Any downsides to using AGM 12V battery?

Discussion in 'Gen 4 Prius Technical Discussion' started by MrFixer, Aug 22, 2025 at 4:11 PM.

  1. MrFixer

    MrFixer New Member

    Joined:
    Feb 24, 2025
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    Location:
    UK
    Vehicle:
    2020 Prius
    Model:
    Excel
    2021 Prius. My 12V battery is starting to drop in voltage more than I'd like after the car is parked for a couple of days. I am considering replacing with AGM (Yuasa brand). I understand AGM has a slightly higher terminal voltage and a lower internal resistance (allowing faster charging on short journey). Sounds good. However are there any downsides to switching to AGM other than higher price?