This is an interesting topic going forward and I'll be curious to see how many models will be going lithium-ion in the future. Author doesn't spend much time on the current Japanese tech which is unfortunate. Japanese seem to be the most advanced in this area from my understanding; would be interesting to know how long their patrols are or expect to be with their upcoming lithium-ion battery subs (likely not public info). Definitely trade-off's with different configurations; but if the Japanese envision their subs going up against Chinese SSN's in the future it is telling that they have so heavily invested in lithium-ion IMO.
Interesting article on the complexities of designing a new type of submarine battery, from the perspective of Attack class, but relevant to all submarine development programs: The Attack-class submarine battery debate: science fiction or engineering? | The Strategist