Start to battle cloud storage issue: that's an idea (10)
I believe the answer is:
brainchild
'that's an idea' is the definition.
(I have seen 'Bright idea' mean 'brainchild' so perhaps 'idea' could also mean 'brainchild')
'start to battle cloud storage' is the wordplay.
'start to' suggests taking the first letters.
'cloud' becomes 'rain cloud' (rain cloud is a kind of cloud).
'storage' becomes 'child' (I can't justify this - if you can you should give a lot more credence to this answer).
The first letter of 'battle' is 'b'.
'b'+'rain'+'child'='BRAINCHILD'
'issue' is the link.
Can you help me to learn more?
(Other definitions for brainchild that I've seen before include "Original idea or work" , "wheeze" , "Bright idea" , "One's original idea" , "Invention" .)