LignoStar supplies premium lignin products as plate expanders for lead batteries. Specifically, StarLig Vanillex can be applied as an additive in this application field. Vanillex N is a highly modified and partially desulfonated sodium oxylignin. It can replace and/or substitute other lignins like e.g. Vanisperse in this application field.
Vanillex N functions as the organic component of the negative plate expander, promoting the formation of optimal crystal sponge structure, and preventing crystal growth. It displays excellent performance extending battery life, low-temperature cranking, and improving reserve performance. The typical dosage rate is 0.2 % to 0.5% by wt.of lead oxide.
The following data and illustrations demonstrate the superior performance properties that Vanillex N brings to battery expanders, by limiting PbSO4 crystal growth in the electrolyte system.
The excellent dispersing effect of Vanillex is attributable to the unique proportion of hydrophilic groups such as sulfonate, carboxyl, phenolic OH groups in relation to the hydrophobic C6 – C3 skeleton. Since Vanillex has been treated with an alkali at high temperature, it has excellent heat-resistance compared with conventional lignosulfonate.
PbSO4 crystal distributions with Vanillex N (fig.1) and without (fig.2) obtained by SEM analysis.
Preventing sulfation and reducing PbSO4 crystal size radically improves battery performance and lifetime durability.
Cross-section of electrode plate (FIB-SEM)
The two images clearly show the reduction in PbSO4 crystal size and a corresponding increase in the reaction surface area with Vanillex N.
This has the effect of dramatically improving the charge acceptance and reserve capacity, whilst also extending cycle life, and is well illustrated by the results obtained for Electrical Property Evaluation by Cyclic Voltammetry. (CV)
The charge/discharge performance is improved significantly with Vanillex N, and shows measurable benefits and improvements compared to Vanisperse A.
Please contact us at any time for price quotes and further information about StarLig products for your specific process at email@example.com or + 31 70 4161 714.