Answer
It is false
Step-by-step explanation:
In old days it was assumed that if we place wooden pallets on concrete. The casing of pallets may break down and their may be leakage of battery. So to protect the case, people placed the pallets on sand or gravel.
Here they use the concept that if you place a glass jar on concrete with a force it may got a crack and if you place this glass jar with same force on sand it will not break.
But it is not true because pallets have strong casing which cant break on placing it on concrete.
Hence When using wooden pallets to store batteries it can be placed anywhere.