Not that there is much meat there, but in case of interest there is a
Sunday press release which is being reported in some press as exonerating the charger. It reads to me more like they ran through tests of electronics removed from the incident JAL aircraft at the manufacturers' sites without finding a detectable fault.
This does go some way to saying the units were not faulty compared to intention. It does nothing to allay concern that the design as intended might place eventually intolerable conditions upon the battery--at least that is my view.