An API Key for Batteries: How Proper Voltage is Powering the Hardware Decade

Greg Slauson, CEO of Proper Voltage, joins Paul Anthony to unpack how a career that started selling structured fixed income on a Goldman Sachs trading floor led him through a solar fintech rocketship, a caramel apple business bought with an SBA loan, and ultimately to building the intelligence layer that turns batteries from a limiter into an enhancer. Greg and Paul have been friends for 12 years, since they were randomly paired as summer intern roommates in Chicago, and Proper Voltage runs its accounting and tax through OpStart, so the conversation moves easily between deep technical detail and the real mechanics of building a company.From there the conversation works through a founder's education the hard way: growing a capital markets team from two people to mid-twenties at GoodLeap, buying and operating Daffy Apple while juggling two other jobs at 90-hour weeks, and learning that a 40-year-old running an HVAC business often knows more than a fresh MBA. Greg is candid about why he walked away from fintech entirely, why he believes the back half of the 2020s belongs to hardware, and how that thesis led him to a six-person battery startup he convinced to hire him.The result is Proper Voltage, the battery operating system that digitally adjusts voltage so products get full power through the entire discharge, enables new chemistries to plug into existing systems, and unlocks features like hot-swapping for robots and data centers. Greg and Paul close on the parts most founders underrate: why working capital is the lifeblood of a hardware business, why chasing headline revenue numbers can quietly kill you, and why the little things, down to whether a deck says Q1 or Q2, compound into trust.In this episode, you'll learn:- Why Greg optimized his early career around who he worked for instead of salary or title, and how that compounded over 12 years- What buying and running a seasonal caramel apple business taught him that 90% transfers to companies of any size- How Proper Voltage turns a battery from a product's limiter into its enhancer, explained through a power drill, a drone, and a Boston Dynamics backflip- Why Greg believes humanoid robotics in 2026 looks like AI did in 2021, and what that means for the next three years- How sodium-ion batteries change the safety and economics of data center backup power- Why working capital, not just margin, determines how far a hardware company can scale without giving away equity- The case for building slow and steady when VCs are pushing for zero-to-$60M in a year