FIELD: analytic chemistry for lead-acid battery manufacture.
SUBSTANCE: in order to essentially raise precision of analytic control of N-phenyl-anthranilic acid content in expander slurry and in active material proposed method involves use of oxidation reaction with potassium dichromate in very acidic medium to form products of pink-violet color and evaluation of mass fraction of N-phenyl-anthranilic acid from calibration curve given in description of invention and constructed including desired amount of its inconvertible bond with optical density of solution ranging between 0.1 and 0.5 percent by weight of lead powder, calculation being made using formula 
where X is mass fraction of N-phenyl-anthranilic acid in expander; T1 is mass of phenyl-anthranilic acid in solution being analyzed, as found from calibration curve, cm3; V1 is volume of source solution, cm3; T2 is mass of expander slurry sample, g; V2 is volume of solution portion being analyzed, cm3.
EFFECT: improved characteristics of storage batteries when running continuously under starter conditions.
1 cl, 2 tbl, 3 ex
