The XSD for the Infinispan subsystem (jboss-as-infinispan_4_0.xsd) says the following about <transaction mode="...">:
Sets the cache transaction mode to one of NONE, NON_XA, NON_DURABLE_XA, FULL_XA.
However, the enum org.jboss.as.clustering.infinispan.subsystem.TransactionMode has the following values:
I.e., the BATCH value is missing from the documentation. Interestingly, BATCH is also used in the default config for all the web and ejb caches.