Following the release of the Canon Speedlite EL-1, it is rumoured that Canon will introduce another EL-series flash later this year.
Unconfirmed reports suggest the next model will be the Speedlite EL-10, and it may have a rechargeable lithium battery, as the EL-1 does.
Given the EL-1 has a super premium price point and the EL-100 is an entry-level product, we expect the EL-10 to sit somewhere in between, as a mid-range product.