Smart Array 5300 Controller Warning

Hi,
I have a Smart Array 5300 controller installed in a Proliant DL580 G2. I was receiving the following warnings in event log.

Source : Storage Agents
Event ID : 1024
Description : Drive Array Accelerator Status Change. The array accelerator board attached to the array controller in Slot 5 has a new status of 4.
(Accelerator status values: 1=other, 2=notConfigured, 3=enabled, 4=tmpDisabled, 5=permDisabled)
[SNMP TRAP: 3038 in CPQIDA.MIB]

Source : Storage Agents
Event ID : 1206
Description : Drive Array Accelerator Battery Failed. The array accelerator board attached to the array controller in Slot 5 is reporting a battery failure.
[SNMP TRAP: 3040 in CPQIDA.MIB]

and the following information log:

Source : Storage Agents
Type : Information
Event ID : 1204
Description : Drive Array Accelerator Status Change. The array accelerator board attached to the array controller in Slot 5 has a new status of 3.
(Accelerator status values: 1=other, 2=notConfigured, 3=enabled, 4=tmpDisabled, 5=permDisabled)
[SNMP TRAP: 3038 in CPQIDA.MIB]

Today is the second time I faced this warning in three days.
I ran HP Array Diagnostic Utility (the report is in the attachment). The accelerator status is showed below:

ACCELERATOR STATUS:
Logical Drive Disable Map: 0xfffffffe
Read Cache Size: 12 MBytes
Posted Write Size: 12 MBytes
Disable Flag: 0x00
Status: 0x00000009
Disable Code: 0x0000
Total Memory Size: 24 MBytes
Battery Count: 2
Battery Status: 0x0003
Parity Read Errors: 0000
Parity Write Errors: 0000
Error Log: N/A
Failed Batteries: 0x0000
Board Present: Yes
Accelerator Failure Map: 0x00000000
Max Error Log Entries: 16
NVRAM Load Status: 0x00
Memory Size Shift Factor: 0x0a
Non Battery Backed Memory: 0 MBytes
Memory State: 0x00

The version firmware is 2.34 so it doesn't seem to be a firmware issue.

Any help gratefully received.

regards,

Anna