grisu raid controller battery needs replacing

[Firefishy]

Grisu RAID controller battery is end-of-life.

/dev/sda: (Smart Array P410) RAID 6 Volume 0 status: OK.
/dev/sg1: (Smart Array P410) Enclosure DL18xG6BP (S/N: ) on Bus 0, Physical Port 1I status: OK.
/dev/sg1(Smart Array P410:0): Non-Volatile Cache status:
                   Cache configured: Yes
                 Total cache memory: 400 MiB
                        Cache Ratio: 25% Read / 75% Write
                  Read cache memory: 100 MiB
                 Write cache memory: 300 MiB
                Write cache enabled: No
   Write cache temporarily disabled
           Temporary disable condition: The posted write cache has been
disabled in a flash-backed write cache module because the
capacitor charge is low.
   Flash backed cache present