Research and Development
Research and development expenses (“R&D”) include expenses incurred in connection with the R&D of our CFV thermal management solution and solid-state rechargeable batteries. R&D expenses are expensed as they are incurred.
For the three months ended September 30, 2021 and 2020, R&D expenses were $481,855 and $51,820, respectively, representing an increase of $430,035 or 830%. For the nine months ended September 30, 2021 and 2020, R&D expenses were $957,579 and $221,524, respectively, representing an increase of $736,055 or 332%. The increase is primarily due to thermal energy management report fees and energy storage development services provided during the period. We expect that our R&D expenses will increase as we expand our future operations.
Selling, General and Administrative
Selling, general and administrative expenses consist primarily of salaries, stock-based compensation, legal and professional expense, marketing and advertising expense, payroll taxes and other benefits, and rent expense.
For the three months ended September 30, 2021 and 2020, selling, general and administrative expenses were $3,104,410 and $832,146, respectively, an increase of $2,272,264 or 273%. The increase is primarily attributable to an increase of approximately $1,116,000 of stock-based compensation, an increase of approximately $252,000 of marketing and advertising expense, an increase of approximately $210,000 for professional fees resulting from engagements for financial services, quality and automation services, as well as an increase of approximately $342,000 in labor costs as the result of sixteen new hires, an increase of approximately $193,000 of miscellaneous expenses, and an increase of approximately $92,000 of travel and entertainment expenses due to the lifting of COVID-19 dining and traveling restrictions.
For the nine months ended September 30, 2021 and 2020, selling, general and administrative expenses were $7,320,524 and $1,719,100, respectively, an increase of $5,601,424 or 326%. The increase is primarily attributable to an increase of approximately $2,511,000 of stock-based compensation, an increase of approximately $1,389,000 of marketing and advertising expense, an increase of approximately $648,000 in labor costs as the result of eight new hires, an increase of approximately $433,000 for professional fees resulting from engagements for financial services, quality and automation services, and an increase of approximately $451,000 of miscellaneous expenses, and an increase of approximately $163,000 of travel and entertainment expenses due to the lifting of COVID-19 dining and traveling restrictions.
Other Expenses
For the three months ended September 30, 2021 and 2020, other income (expenses) were $44,550 and $(201,739), respectively, representing an increase of $246,289. The increase in other income is primarily due to no 2021 charges for amortization of debt discount and the increased income from the change in fair value of accrued issuable equity of $45,600.
For the nine months ended September 30, 2021 and 2020, other expenses were $337,153 and $328,170, respectively, representing an increase of $8,983 or 3%. The increase in other expense is primarily due to the 2021 debt redemptions costs of $140,000 associated with the repayment of notes payable, and an increase of $50,000 of expenses related to the change in fair value of accrued issuable equity, partially offset by a decrease of amortization of debt discount of $179,000 during the nine months ended September 30, 2021.
Liquidity and Capital Resources
As of September 30, 2021, we had a cash balance of $10,990,056 and working capital of $10,659,878. We incurred a net loss of $7,837,798 during the nine months ended September 30, 2021 and had an accumulated deficit totaling $19,084,206 as of September 30, 2021. While the Company anticipates it will continue to incur operating losses and use cash in operating activities for the near future, the Company believes that its current working capital is sufficient in comparison to its anticipated cash usage for a period of at least twelve months subsequent to the filing date of these financial statements.
For the nine months ended September 30, 2021 and 2020, cash used in operating activities was $5,394,935 and $2,076,035, respectively. Our cash used in operations for the nine months ended September 30, 2021 was primarily