Recommended · for some experience
Are over-discharged lithium cells safe? (And how to test for damage.)
Why people recommend it
Big Clive tests whether over-discharged lithium cells are safe to recharge and how to check them for damage; cited in debates about deep discharge.
Watch for: slow, low-current recovery charging
In their words
Bigclive says there won't be any internal short circuit before the cells have been reverse charged to -12% which equals to about negative 2 volts.
Oskar Skog on electronics.stackexchange.com, Mar 2018. CC BY-SA.
Damage (and not quote unquote "danger", per se) _seems_ to not happen if an empty battery is recharged with low currents, according to oh about five million accounts enumerated as comments to this video.
Martin Andersson on electronics.stackexchange.com, Aug 2023. CC BY-SA.
