An extract from the senate hearing is presented here on...

An extract from the senate hearing is presented here on youtube 
https://www.youtube.com/watch?v=wv0PHIo1zzo

"Since October 2017, planned lithium ion battery capacity in the pipeline for the period 2019-2028 has risen from 289GWh to 1,549GWh (1.54TWh) in Benchmark Mineral Intelligence’sFebruary 2019 Assessment. This expanded capacity is the equivalent of 23-24 million sedan-sized electric vehicles."

Interesting to view the chart here of EV market share (from Colin Mckerracher at BNEF) - shows the US late to the party but a dramatic uptick in second half of last year (presumably as Tesla started shipping in earnest)
https://twitter.com/colinmckerrache/status/1092904307052015616

It is very hard to see Lithium production keeping pace with demand - even harder to see how anyone can take oversupply scenarios seriously...