Yes, it is technically possible to perform welding using batteries as a power source. This method is often used as a quick or emergency solution, typically involving automotive batteries connected in series or parallel to provide enough voltage and current for striking an arc.
Using batteries for welding relies on their ability to deliver high current, which is necessary to generate the heat required to melt metal and welding rods. However, this approach comes with significant limitations and challenges compared to using a dedicated welding machine.
Key Considerations for Battery Welding
While seemingly simple, welding with batteries presents several critical factors that impact safety, weld quality, and the batteries themselves.
Amperage Control - A Major Challenge
One of the primary drawbacks of using batteries for welding is the lack of control over the amperage. When you use batteries directly, the amount of current flowing is largely determined by the battery's capacity, voltage, and the resistance of the welding circuit (including the rod and workpiece).
- Impact on Welding Rods: As highlighted by references, if you use thin welding rods, the absence of amperage control means they "will basically evaporate and you will get a shallow, crappy weld." This happens because the uncontrolled high current quickly melts the rod material without achieving proper penetration or fusion with the base metal.
- Quick Fix: To address this issue, a common suggestion is to use a thicker welding rod. A thicker rod can handle the higher, uncontrolled current flow more effectively, allowing for a more stable arc and potentially a slightly better weld, although still often considered "quick and dirty."
Other Factors to Consider
Beyond amperage control, battery welding involves other important points:
- Weld Quality: Welds produced using batteries are typically inconsistent and of lower quality compared to those made with proper welding equipment. Achieving good penetration, consistent bead shape, and strong fusion is difficult without precise control over voltage and amperage.
- Safety Risks: Working with high-current battery setups carries significant safety hazards, including the risk of electric shock, sparks causing fires, battery explosions (due to overheating or short circuits), and the release of hazardous fumes.
- Battery Health: Using batteries for welding puts an extreme load on them. It can quickly discharge, overheat, or even permanently damage the batteries, reducing their lifespan or rendering them unusable for their original purpose.
- Voltage Requirements: Typically, multiple 12-volt car batteries are connected in series (e.g., two for 24V, three for 36V, or four for 48V) to achieve a voltage high enough to strike and maintain an arc with common welding rods.
In summary, while it is possible to weld using batteries, it is generally not recommended for producing reliable or safe welds and should only be considered as a last resort in situations where no proper welding equipment is available. The lack of amperage control is a major technical hurdle, directly affecting the quality and efficiency of the welding process, as evidenced by the need to use thicker rods just to make it somewhat functional.
