The engineering behind every glass.
Electrolysis has been understood for over a century — what's changed is the engineering. Here's a plain-language look at how hydrogen water is actually produced, and why membrane technology and chamber design matter more than most labels let on.
Behind every glass of hydrogen-rich water is a piece of engineering doing real chemistry — splitting a water molecule apart and capturing the hydrogen before it escapes. The general idea, electrolysis, is more than a century old. What varies dramatically between products is how that electrolysis is engineered: what kind of membrane is used, whether the chambers are separated, and how the system prevents unwanted byproducts. Here's how it actually works.
Electrolysis is the process of using an electrical current to drive a chemical reaction that wouldn't otherwise happen on its own. In the case of water (H₂O), running a direct current through it causes the water molecule to split into its two components: hydrogen gas (H₂) at one electrode and oxygen gas (O₂) at the other. This is the same basic chemistry taught in introductory science classes, just engineered at a scale and design level suited for producing drinking water enriched with dissolved hydrogen.
An electrolysis cell has two electrodes — a cathode (negative) and an anode (positive) — submerged in water. When current flows, hydrogen gas bubbles form at the cathode and oxygen gas forms at the anode. In a hydrogen water system, the water surrounding the cathode becomes enriched with dissolved hydrogen, which is then either directed into the water you drink or allowed to dissolve back into the source water, depending on the system's specific design.
The engineering challenge is keeping this process clean and efficient: maximizing how much hydrogen ends up dissolved in the water, minimizing gas that simply escapes as bubbles, and preventing the oxygen side of the reaction — along with any minerals or contaminants in the source water — from contaminating the hydrogen-rich side.
Want to understand how hydrogen concentration is measured or how hydrogen water compares with inhalation? Explore our guides on PPM vs. PPB and Hydrogen Water vs. Hydrogen Inhalation.
SPE stands for Solid Polymer Electrolyte. Older electrolysis designs often relied on a liquid electrolyte solution to help conduct ions between electrodes. SPE technology replaces that liquid electrolyte with a thin solid polymer membrane that performs the same ion-conducting function. This matters because a solid membrane is more stable, easier to keep clean, and doesn't introduce a separate liquid chemical into the system that would need to be kept away from the drinking water itself.
PEM stands for Proton Exchange Membrane (also sometimes called Polymer Electrolyte Membrane), and it's a specific, well-established category of SPE technology. A PEM allows protons — positively charged hydrogen ions — to pass through the membrane from one side to the other, while blocking electrons and gas molecules from crossing. That selective permeability is exactly what allows hydrogen gas to form and stay concentrated on one side of the system while oxygen forms and stays separated on the other. PEM technology is widely used across hydrogen-related applications beyond just water systems, including hydrogen fuel cells, because the underlying separation principle is so effective.
A single-chamber electrolysis design runs the entire reaction in one space, which means hydrogen and pH control (the acid/alkaline balance of the resulting water) are coupled together as one reaction. A dual-chamber — or dual-cell — design separates these functions: one chamber or cell handles the primary electrolysis, and a second, dedicated chamber or booster cell focuses specifically on maximizing dissolved hydrogen output. This decoupling gives engineers more precise control over the final hydrogen concentration without being constrained by whatever pH level the water lands on.
Dual-chamber and membrane-separated designs are also generally better positioned to minimize byproduct formation, since the physical separation reduces the chance of the hydrogen-rich water coming into contact with the oxygen-generating side of the reaction or with contaminants mobilized from the source water.
Portable hydrogen water bottles are compact, battery-powered devices, usually producing a single serving of hydrogen-rich water on demand by running a small electrolysis cell for a few minutes directly inside the bottle. Their strength is convenience — no plumbing, no installation, easy to bring along during travel or a workday. Their tradeoff is generally a smaller electrolysis cell and less robust filtration compared to larger countertop or under-counter systems, which can mean more variability in dissolved hydrogen output between units and between uses.
Home and in-studio systems — countertop or under-counter units connected to a water line — generally use larger, more sophisticated electrolysis architecture, often including multi-stage filtration ahead of the electrolysis chamber, membrane-separated dual-cell or dual-chamber designs, and more consistent power delivery to the electrodes. The larger footprint allows for more robust engineering overall, which is generally reflected in higher and more consistent dissolved hydrogen output session to session. At Naturally Bronzed, our in-studio hydrogen water is produced through a Tyent Hybrid ionizer system using this kind of dual-cell architecture.
Responsible manufacturers test finished output using the same measurement tools discussed elsewhere in our hydrogen knowledge center — drop reagent kits, dissolved hydrogen meters, and gas chromatography for lab-grade verification. Testing at the point of production (rather than relying on a theoretical maximum output the system is capable of under ideal conditions) gives a more honest picture of what a system delivers in real, everyday use. Some manufacturers also submit their systems for independent third-party certification, adding a layer of verification beyond their own internal testing.
All electrolysis-based hydrogen systems work essentially the same way.
Engineering varies significantly — single-chamber versus dual-chamber design, SPE/PEM membrane quality, and filtration all meaningfully affect output, consistency, and byproduct risk.
Electrolysis is inherently unsafe because it involves running current through water.
Electrolysis is a well-established, widely used chemical process. Byproduct concerns like chlorine or ozone formation are specifically associated with poorly designed single-chamber systems, not electrolysis as a category — well-engineered membrane-separated systems are designed to minimize that risk.
SPE stands for Solid Polymer Electrolyte. In hydrogen water systems, it refers to a thin solid membrane that conducts ions during electrolysis without requiring a liquid electrolyte solution, allowing hydrogen and oxygen gas to be separated cleanly at the membrane surface.
PEM stands for Proton Exchange Membrane (sometimes called Polymer Electrolyte Membrane). It is a specific type of solid polymer membrane that allows protons (hydrogen ions) to pass through while blocking electrons and gases, which is what allows hydrogen and oxygen produced during electrolysis to stay physically separated.
Membranes like SPE/PEM keep the hydrogen gas produced at one electrode physically separated from the oxygen and any byproducts produced at the other electrode. Without that separation, gases could recombine or contaminants from the electrolysis process could end up dissolved in the drinking water itself.
Yes, depending on the system's design. Poorly designed or single-chamber electrolysis systems can generate unwanted byproducts, such as chlorine or ozone, particularly when using tap water with dissolved minerals and chlorides. Well-engineered dual-chamber or membrane-separated systems are specifically designed to minimize this risk.
Portable hydrogen water bottles are typically small, battery-powered, and generate a single serving on demand, making them convenient for daily or on-the-go use. Home and in-studio systems are larger, plumbed-in or countertop units capable of higher and more consistent hydrogen output, generally with more robust filtration and membrane technology.
If you're interested in experiencing fresh, in-studio hydrogen water regularly, the All-Access Wellness Membership ($249/month) includes access to hydrogen therapy alongside our other recovery modalities. See our membership options for details.
H₂ Inhalation · Fresh H₂ Water $8/18oz bottle · In-studio at 200 Middle Neck Rd, Great Neck, NY.
Book Your Session ↗Serving Great Neck, Manhasset, Roslyn, Port Washington, New Hyde Park, Lake Success, Little Neck, Bayside, and surrounding Long Island communities.