June 4 (Reuters) - Occidental Petroleum ( OXY ) said on

Tuesday it had entered into a joint venture with Berkshire

Hathaway's ( BRK/A ) energy unit to extract lithium.

The energy producer said it would use its technology to

extract and commercially produce high-purity lithium compounds

at Berkshire's geothermal facility in California.

Lithium is the key metal used in the production of batteries

for electric vehicles, consumer electronics and energy grid

storage.

Oil majors are investing in the electrification sector as

governments in the United States and Europe establish programs

to promote the wider use of EVs and reduce fossil-fuel

consumption.

Exxon Mobil ( XOM ) has plans to start producing lithium

from sub-surface wells by 2027, while European oil rivals BP

and Shell have invested in EV charging stations

as part of their energy transition strategies.

Occidental said the project would demonstrate the

feasibility of using its unit's direct lithium extraction

technology to produce lithium in an environmentally safe manner.

BHE Renewables, Berkshire's energy unit, operates 10

geothermal power plants in California's Imperial Valley that can

process 50,000 gallons of lithium-rich brine per minute to

produce 345 megawatts of clean energy.

Upon successful demonstration, BHE Renewables plans to

build, own and operate commercial lithium production facilities

in California's Imperial Valley.