What are HHO dry cells and HHO wet cells
HHO dry cells and HHO wet cells are two types of devices used to produce hydrogen and oxygen gas through the electrolysis of water. They are all alkaline hydrogen generators.
HHO Dry Cells:
- Use a series of stacked plates separated by gaskets, creating small cavities for water to flow between the plates.
- Electrolyte is confined within these cavities, preventing free movement of liquid.
- More efficient design as current is forced to flow through the plates rather than around them.
- Compact and safer due to reduced risk of electrolyte leakage.
- Typically use stainless steel plates and neoprene gaskets.
- Water flows through small holes in the plates, allowing for continuous gas production.
HHO Wet Cells:
- Consist of electrodes (plates or wires) submerged in a container filled with electrolyte solution.
- Electrolyte is free to move within the container.
- Less efficient as current can “bleed off” the edges of the plates, taking the path of least resistance.
- Generally larger and potentially riskier due to the presence of free-flowing liquid electrolyte.
- Examples include mason jar designs with stainless steel wires or stacked plates in water filter housings.
From Youtuber ：Inventive – Water fuel
Whether it’s dry cells or wet cells, they are all alkaline hydrogen generators. Their efficiency is much lower than that of PEM hydrogen generators. Their energy consumption is much higher than that of PEM hydrogen generators. Additionally, due to the need to add a high concentration of KOH solution, the resulting HHO gas carries strong alkaline substances. Prolonged use can damage the engine. Moreover, various metal salts can easily form and adhere near the metal plates, reducing the overall efficiency of the system. As a result, the entire system often needs to be disassembled for maintenance, which is really troublesome. Additionally, their efficiency is also far inferior to that of PEM hydrogen generators.
How HHO car kits work in vehicles
Some people believe that HHO is used to produce hydrogen from water, which is then used as fuel to drive the vehicle. This is incorrect and does not comply with physical principles.
At present, there are indeed vehicles that are completely powered by hydrogen. For example, Toyota and Kia have corresponding hydrogen-powered vehicles. They store hydrogen in the car beforehand and then use a hydrogen fuel cell to convert the hydrogen into electricity, which is used to drive the vehicle, similar to how current new energy vehicles work.
However, HHO car kits use PEM hydrogen generators, utilizing the vehicle’s excess power (0-80W) to produce hydrogen and oxygen. The hydrogen and oxygen enter the engine, allowing gasoline or diesel to burn more completely, thereby improving fuel efficiency. It does not create energy out of thin air to drive the car.
Why do hydrogen and oxygen allow fuel to burn more completely?
Hydrogen is a renewable green energy source, with a diffusion rate four times that of gasoline and a flame propagation speed five times that of gasoline. These characteristics make hydrogen an ideal alternative fuel for spark-ignition internal combustion engines. Unlike other alternative fuels, hydrogen does not contain carbon atoms, so it does not produce hydrocarbon, carbon monoxide, or carbon dioxide emissions during combustion. Furthermore, stable combustion can reduce nitrogen oxide emissions.
| Fuel | Hydrogen | Gasoline | Diesel | Natural Gas |
| Air fuel ratio | 34.3 | 14.6 | 14.5 | 17.1 |
| Minimum ignition energy（mJ) | 0.02 | 0.24 | – | 0.28 |
| Autoignition Temperature（K） | 858 | 530 | 493 | 632.2 |
| Flame propagation velocity（cm/s） | 237 | 41.5 | 30 | 37.3 |
| Burning concentration limit（Air vol%） | 4.1-75 | 1.5-7.6 | 0.7-5 | 5.1-15 |
| Net heat value（MJ/kg） | 120 | 44 | 42.7 | 32.5 |
The high diffusivity of hydrogen makes the fuel mixture in internal combustion engines more uniform, promoting rapid and complete fuel combustion. Therefore, internal combustion engines using hydrogen have shorter combustion times compared to traditional gasoline and diesel engines, ultimately improving thermal efficiency.
In summary, hydrogen generator car kits are a promising alternative to traditional engines. They can improve fuel efficiency, reduce emissions, and provide a cleaner solution for transportation. We conducted a test on this.
