I'm assuming that you mean 9.9 × 10⁹ kg of economically-extractable-now reserves and 2.55 × 10¹⁰ kg of potentially economic reserves, not 2575.5 kg, which is what 2.55 × 1010 would work out to.
The estimates of lithium abundance in the earth's crust have a low end of 20 ppm. The crust averages about 40 km thick and 3 g/cc in the 29% of the Earth that has continents, which works out to 1.5 × 10¹⁴ m², 5.9 × 10¹⁸ m³, 1.8 × 10²² kg of rock, and 3.6 × 10¹⁷ kg of lithium. This is a bit over ten million times more lithium than the USGS's estimated "potentially economic world lithium reserves".
There's also 2.3 × 10¹⁴ kg of lithium dissolved in seawater, but that is a much smaller amount than the amount in the crust. However, it's still ten thousand times larger than the USGS's estimate.
I think world lithium production is actually about 4.3 × 10⁷ kg per year (see https://en.wikipedia.org/wiki/Lithium#Reserves) which would take 200 years to exhaust the "economically extractable now" number you give (rather than the 500 years you'd get with the numbers you give). It seems like a safe bet that some new mining technologies will become available before even 2100, let alone 2219.
How much energy is that? https://en.wikipedia.org/wiki/Energy_density#Table_of_energy... says Li-ion batteries contain 0.36–0.88 MJ/kg, or slightly higher if you only count the mass of the lithium rather than the entire battery. Conservatively taking 0.36 MJ per kg of lithium (which assumes battery technology doesn't improve — almost-nonrechargeable lithium-metal batteries get five times that much energy per kg of lithium), the 9.9 × 10⁹ kg of lithium "economically extractable now" would hold 3.6 petajoules; the 2.3 × 10¹⁴ kg of lithium in seawater would hold 83 exajoules; and the 3.6 × 10¹⁷ kg of lithium in the continental crust would hold 130 zettajoules.
Current world marketed energy consumption is on the order of 5.7 × 10²⁰ joules per year (https://en.wikipedia.org/wiki/World_energy_consumption), which is 18 terawatts. Incident solar power on the Earth (the Kardashev Type 1 benchmark) is 130 petawatts. So the 3.6 PJ of "economically extractable now" lithium is only three minutes of world marketed energy consumption, but the 83 EJ of seawater lithium is about 1.7 months of world marketed energy consumption. Even so, that's only 10 minutes of total terrestrial insolation. But the 130 zettajoules of continental crustal lithium is 12 days' worth of total terrestrial insolation.
So, that's the basis of my conclusion about terrestrial lithium being sufficient to provide energy storage until we pass Kardashev Type 1. Can you check my calculations, please?