A method of making a nonwoven fiber mat having a Cobb 60 degree of less than 1, determined in accordance with ISO 535, for use in a lead-acid battery, the method comprising: (i) adding a binder composition to a wet nonwoven fiber mat, wherein: - the wet nonwoven fiber mat comprises a first plurality of first glass fibers and a second plurality of second glass fibers, said wet nonwoven fiber mat containing 10 wt.% and more of water, - the first plurality of first glass fibers has nominal diameters of less than 5 μm, - the second plurality of second glass fibers has nominal diameters of greater than 6 μm, and - the first plurality of first glass fibers comprises between 10% and 50% by weight of the combined weight of the first plurality of first glass fibers and the second plurality of second glass fibers; and - the wet nonwoven fiber mat is produced by mixing the first plurality of first glass fibers and the second plurality of second glass fibers to form a slurry prior to adding the binder composition, and maintaining a pH of the slurry at 5 or higher, (ii) curing the binder composition to produce the nonwoven fiber mat, wherein: the nonwoven fiber mat has a wick height of between 1 cm and 5 cm according to method ISO8787, and the nonwoven fiber mat has a total normalized tensile strength of greater than 8.896 (N/2.54cm)/(453g/9.29m 2) [2 (lbf/in)/(lb/sq)], said normalized tensile strength is derived from the sum of the average machine direction tensile strength (Ibf/in) and the average cross machine direction tensile strength (lbf/in), divided by the mat weight (lb/sq) of 10 pieces and the tensile strength is measured using ASTM D5035 - 11 Reapproved 2015. (i) adding a binder composition to a wet nonwoven fiber mat, wherein: - the wet nonwoven fiber mat comprises a first plurality of first glass fibers and a second plurality of second glass fibers, said wet nonwoven fiber mat containing 10 wt.% and more of water, - the first plurality of first glass fibers has nominal diameters of less than 5 μm, - the second plurality of second glass fibers has nominal diameters of greater than 6 μm, and - the first plurality of first glass fibers comprises between 10% and 50% by weight of the combined weight of the first plurality of first glass fibers and the second plurality of second glass fibers; and - the wet nonwoven fiber mat is produced by mixing the first plurality of first glass fibers and the second plurality of second glass fibers to form a slurry prior to adding the binder composition, and maintaining a pH of the slurry at 5 or higher, - the wet nonwoven fiber mat comprises a first plurality of first glass fibers and a second plurality of second glass fibers, said wet nonwoven fiber mat containing 10 wt.% and more of water, - the first plurality of first glass fibers has nominal diameters of less than 5 μm, - the second plurality of second glass fibers has nominal diameters of greater than 6 μm, and - the first plurality of first glass fibers comprises between 10% and 50% by weight of the combined weight of the first plurality of first glass fibers and the second plurality of second glass fibers; and - the wet nonwoven fiber mat is produced by mixing the first plurality of first glass fibers and the second plurality of second glass fibers to form a slurry prior to adding the binder composition, and maintaining a pH of the slurry at 5 or higher, (ii) curing the binder composition to produce the nonwoven fiber mat, wherein: the nonwoven fiber mat has a wick height of between 1 cm and 5 cm according to method ISO8787, and the nonwoven fiber mat has a total normalized tensile strength of greater than 8.896 (N/2.54cm)/(453g/9.29m 2) [2 (lbf/in)/(lb/sq)], said normalized tensile strength is derived from the sum of the average machine direction tensile strength (Ibf/in) and the average cross machine direction tensile strength (lbf/in), divided by the mat weight (lb/sq) of 10 pieces and the tensile strength is measured using ASTM D5035 - 11 Reapproved 2015. the nonwoven fiber mat has a wick height of between 1 cm and 5 cm according to method ISO8787, and the nonwoven fiber mat has a total normalized tensile strength of greater than 8.896 (N/2.54cm)/(453g/9.29m 2) [2 (lbf/in)/(lb/sq)], said normalized tensile strength is derived from the sum of the average machine direction tensile strength (Ibf/in) and the average cross machine direction tensile strength (lbf/in), divided by the mat weight (lb/sq) of 10 pieces and the tensile strength is measured using ASTM D5035 - 11 Reapproved 2015.