"record quantity" is grammatically correct and can be used in written English.
It is typically used to refer to a very large or unprecedented amount of something. Example: "The company reported a record quantity of sales for the year, exceeding all previous records by a significant margin."
Last Friday, the US Federal Reserve reported a record quantity of cash on the books of US businesses (over $2tn).
At the same time that the young critics of the French New Wave were consuming Hollywood movies in record quantity and preparing to make films that reflected their consuming passion, Tashlin was making movies that looked at movie fandom ("Hollywood or Bust"), rock and roll ("The Girl Can't Help It"), and advertising and television ("Will Success Spoil Rock Hunter?").
An Icelandic company, Hvalur, caught over a hundred fin whales in 2014, and exported a record quantity of 2071 tonnes in a single shipment in 2014.
It forecasts both global exports and consumption to be of "record quantities".
GDP grew by over 5%, inflation was less than 10%, and foreign direct investment arrived in record quantities.
The UK is selling record quantities of arms – including missiles, bombs and grenades – to countries listed by the Foreign Office as having dubious human rights records.
Last year China imported record quantities of rapeseed and soybeans, because foreign oilseed production is cheaper and the quality often higher than that of domestically grown crops.
Meanwhile, Mexican factories are exporting record quantities of televisions, cars, computers and appliances, replacing some Chinese imports in the United States and fueling a modest expansion.
It has caught several of the top gang leaders, extradited about 50 suspected traffickers to the United States and seized record quantities of drugs.
The extreme weather – which is killing record quantities of salmon in rivers around the Northwest — was just another reason why we were prepared to stay as long as required.
As record quantities of illegal drugs are being intercepted in Arizona, those involved in taking people and drugs across the border are increasingly concentrating on the more rewarding smuggling of Chinese immigrants, said David Jimarez, a spokesman for the Border Patrol.
