According to the unofficial reports from China, via the Moneyball, in February 2020 only LG Chem was supplying lithium-ion batteries for the Tesla Gigafactory 3.

"LG Chem supplied all Tesla Model 3 February installed batteries, #China media reports citing #auto OEM conformity certificates data.

Earlier reports based on vehicle production showed Panasonic as Tesla's Feb supplier."

The attached table shows battery capacity for Made-in-China (MIC) Model 3 during the first two months of 2020:

January

Panasonic: 83.32 MWh

LG Chem: 54.39 MWh

Panasonic: 83.32 MWh LG Chem: 54.39 MWh February

Panasonic: 0 MWh

LG Chem: 201.92 MWh

Panasonic: 0 MWh LG Chem: 201.92 MWh Total

Panasonic: 83.32 MWh

LG Chem: 256.31 MWh

About 200 MWh (200,000 kWh) is equivalent to 4,000 50 kWh battery packs (please note that we don't know exactly the capacity of the Model 3 Standard Range Plus in China and this is just an example).

For comparison, Tesla reportedly delivered some 3,958 Model 3 in February, while the production was 3,898. All the numbers seem pretty close.

If true, the battery supply data would also indicate that Panasonic was supplying batteries only for the ramp-up phase.

The previous rumors, provided by the Moneyball, were that LG Chem will supply 10-13 GWh of cells (NMC 811 chemistry). That would be enough for 200,000-260,000 50 kWh packs (proportionally less if the pack capacity is higher).

Regardless of the report, we guess that Tesla probably will need more than 10 GWh of battery cells annually in the first full year of operation in China.