The first of two StarPlus Energy battery factories in Kokomo, Indiana, began domestic production of lithium-ion batteries for electric vehicles (EVs) in March 2025. PENETRON ADMIX SB, a crystalline waterproofing admixture, was used to protect key concrete structures exposed to the area's high groundwater levels.

The largest city in Howard County in north central Indiana, Kokomo is home to about 60,000 people and has a long tradition in auto manufacturing. The city is now set to become a hub for electric vehicle battery manufacturing with the construction of two StarPlus Energy battery gigafactories.

StarPlus Energy is a joint venture between Stellantis, a global auto manufacturer with over a dozen well-known brands, and Samsung SDI, a Korean battery and electronic materials manufacturer. The joint venture's new Kokomo plant, a $2.5 billion gigafactory, is the first of two electric vehicle battery production facilities situated in Kokomo. The inaugural multimillion-square-foot facility is set for an annual production capacity of 23 gigawatt hours (GWh), increasing to 33 GWh within a few years.

A second battery production facility, a $3.2 billion investment, is set to open in 2027. The combined annual production capacity of both gigafactories will reach 67 GWh. The two StarPlus Energy plants represent a crucial element of a strategy to supply battery modules for the growing range of EV models to be produced at Stellantis' North American auto assembly plants.

"Because the elevator pits and elevator shafts are the deepest below-grade concrete structures of the Kokomo plant, they are also exposed to high groundwater levels. If not treated with a waterproofing solution, these concrete structures can rapidly become vulnerable to moisture infiltration due to the hydrostatic pressure of the groundwater," adds Richard Farmer, Eastern Region Sales Manager for Penetron USA. "This can rapidly lead to corrosion of the embedded reinforcement steel and serious deterioration of the whole structure."

After discussion with the Penetron team, imi, the ready-mix concrete supplier, specified PENETRON ADMIX SB, a crystalline waterproofing admixture, as the optimal concrete waterproofing solution. PENETRON ADMIX SB was added to the concrete mix during the batching phase.

Once exposed to moisture, the active ingredients in Penetron's admixture penetrate the concrete matrix to form a non-soluble crystalline network throughout the pores and capillary tracts of the concrete structure. This crystalline network reduces concrete permeability, regardless of hydrostatic pressure levels – effectively blocking any water from moving through the concrete and avoiding deterioration of hard to reach below-grade structures, like an elevator pit.

"Last but not least, the self-healing capability of the PENETRON ADMIX SB-treated concrete mix used at the StarPlus Energy site will ensure long-term durability for the plant's concrete structures," adds Richard Farmer. "The need for any future concrete-related maintenance is virtually eliminated."

The Penetron Group is a leading manufacturer of specialty construction products for concrete waterproofing, concrete repairs, and floor preparation systems. The Group operates through a global network, offering support to the design and construction community through its regional offices, representatives, and distribution channels.