Green’s Dictionary of Slang

batch n.¹

a quantity of liquor; thus a heavy night’s drinking.

1759		J. Townley High Life Below Stairs I ii: Sir Harry, we’ll have a noble Batch—I have such Wine for you!
c.1786, 1796		Grose Classical Dict. of the Vulgar Tongue (ms additions, 3rd edn) n.p.: Batch. We had a pretty batch of it last night; we had a hearty dose of liquor. Batch originally means the whole quantity of bread baked at one time in an oven.
1811		Lex. Balatronicum.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue.
1950		Goldin et al. DAUL 24/1: Batch. (P) A quantity of home brew. ‘The P.K. (Principal Keeper) caught Mike with a batch of potato water (a fermentation of potato peelings, yeast, and sugar).’.

SE in slang uses

In phrases

run off a batch by hand (v.)

to masturbate.

2003

Number One Adult Sexual Health Terms Advisor 🌐 Masturbation Slang Unisex Terms: [...] run off a batch by hand.