Are you a DIY enthusiast and hobbyist that require connecting multiple battery cells but is worried about using the cumbersome soldering tool? Then you need to enter the world of battery spot welders.
A good spot welder can make your battery connections simple and elegant. Some spot welder models are flexible, and you can use them to connect battery cells and join metal strips or sheets up to a thickness of 0.3 mm. The good thing about a spot welder is it is affordable.
If you have an artistic mind, you can create simple metal arts using thin metal, and all you need is a pair of good scissors/snips, a metal sheet, and a suitable spot welder.
Learning spot welding is not difficult. Once you master this common welding method and be comfortable using it, you will be able to connect batteries easily and efficiently and work on any circuit connections.
After careful research, we have compiled some of the bestselling spot welders on the market and provided a few buying tips to help you making the decision to buy a spot welder simple and easy.
Take a look at our following reviewed products and see which one could be your next battery spot welder! Let us begin.
Best Battery Spot Welder in 2024
- SUNKKO 737G+ Battery Spot Welder (Best Battery Spot Welder Overall)
- Mophorn 709A Pulse Spot Welder (Runner Up 1)
- SUNKKO 709AD+ Battery Spot Welder (Runner Up 2)
- SQ‑SW1 Spot Welder (Best Portable Spot Welder)
- Kerpu Rechargeable Portable Spot Welder (Best Mini Spot Welder)
- TUNFOU Portable Spot Welder (2nd Best Mini Spot Welder)
Best Battery Spot Welder Overall
SUNKKO 737G+ Battery Spot Welder
SUNKKO 737G+ Spot Welder is a medium-budget and portable spot welder. The welder input power is AC 110V, 50-60Hz, with a welding current of 120-1200 amperes. The welder’s corresponding single pulse time is 5 ms, and the maximum pulse quantity is 18.
The welder can weld pure nickel, nickel-plated steel, iron, etc. However, it cannot weld copper and aluminum. This model is good for building large rechargeable lithium battery packs.
SUNKKO 737G+ is an improvement over the basic model 737G, and it is specially designed for battery welding (18650, 14500, etc.).
The welding thickness range is 0.03 to 0.3 mm for fixed copper head and 0.03 to 0.2 mm for mobile welding pen, and the welding thickness of the pure nickel is from 0.03 to 0.15 mm.
The welder features a pressure regulator knob, welding pen with a length of approximately 22.8″, and adjustable welding needle distance of 2 to 7 mm. When the foot pedal is plugged in, it is MT (manual trigger) mode; otherwise, it is AT (auto-trigger) mode.
The built-in temperature sensor and intelligent cooling system automatically work according to the internal temperature of the machine.
The product dimensions: 5.5ʺ ×10ʺ ×8ʺ and weight is 15.6 pounds.
Pros
• AC 110V, 50-60Hz input.
• Portable, weighing 15.6 pounds.
• Has both fixed head and mobile welding pen facility.
• Can weld pure nickel, nickel-plated steel, iron, etc.
• Foot pedal facility.
• Soldering function can heat up to 300°C within 7-8 seconds;
• LCD digital display and setting.
• SUNKKO 737G+ comes with one year warranty.
Cons
• Costlier for beginners and hobbyists.
Runner Up 1
Mophorn 737G+ Spot Welder
Mophorn 737G Pulse Spot Welder is a medium-budget and portable spot welder. The welder input power is AC 110V, 50-60Hz, welding current is 120-1200 amperes, and the corresponding pulse time is 2-18 ms.
The welder has upgraded LED lighting, and the high brightness LED provides good lighting during welding. The enhanced LED lighting version makes this machine easy to operate for low vision users and helps welding in a low brightness environment.
The digital LCD panel shows pulse quantity and current when doing spot welding, and the LCD panel allows you to set current and pulse easily and quickly.
Mophorn 737G+ can be used for various sizes of battery packs, button battery, polymer battery and board, Apple mobile phone camera, stainless steel hardware, stainless steel mesh, etc.
The welder enables you of welding workpieces of different thicknesses and to achieve good and reliable solder joints. The welder is capable of welding nickel-plated steel strips within 0.05-0.35mm or between 0.05 and 0.25 mm for pure nickel strips.
This spot welder has a precise welding pen with a double-click welding needle that provides more balanced solder joints, makes the one-hand operation possible, adjusts solder joint distance, and avoids flashover welding.
Pros
• AC 110V, 50-60Hz input.
• Portable, weighing 12.08 pounds.
• Touching Automatic Welding, which automatically triggers the spot welding without the need of footswitch control.
• Welding nickel-plated steel strips within 0.05-0.35 mm thickness.
• Integrated welding pen.
• LCD digital display and setting.
• LED working lights.
Cons
• Brand reliability is unknown.
• Costlier for beginners and hobbyists.
Runner Up 2
SUNKKO 709AD+ Battery Spot Welder
SUNKKO 709AD+ Spot Welder has a new panel design with an intelligent function (for the welding pen only) to improve the efficiency of the battery pack welding process. With input voltage AC 110 V, welding current is 50 to 800 A, single pulse time is 5ms, and maximum pulse quantity is 18. This welder is equipped with a solder
The built-in temperature control system enables continuous spot welding by a built-in temperature sensor and the cooling system that works automatically according to the internal temperature of the welder. The real-time pulse display provides you with the machine’s actual welding status.
The range of welding thickness is 0.03 – 0.3 mm for the fixed copper head and 0.03 – 0.2 mm for the welding pen, and the welding thickness of the pure nickel is 0.03 to 0.15 mm.
This spot welder is specifically designed for battery welding (18650, 14500, and other lithium batteries) and the built-in LED helps to work in low light and nights.
The soldering temperature range of 150 to 500℃ (up to 300°C within 7 to 8 seconds), soldering station power: 50 W, and output voltage: DC 20 V.
You have three methods for improving spot welding performance:
- Adjusting welding current (1 to 8 levels optional).
- Adjusting pulse quantity (2 to 18 optional).
- Pressure knob.
The product dimension: 5.5ʺ × 10ʺ × 8ʺ and weight is 15.6 pounds.
Pros
• AC 110 V input.
• Has both fixed head and mobile welding pen facility.
• Lightweight 15.6 pounds.
• Built-in LED for working in low light and night.
• Foot pedal facility.
• Equipped with a solder.
• SUNKKO 709AD+ comes with one year warranty.
Cons
• Soldering pen is not as efficient as it should be.
Best Portable Spot Welder
SQ‑SW1 Spot Welder
SQ‑SW1 is a medium-budget, lightweight, portable spot welder. Convenient to use and can be installed easily and quickly. The welder input voltage is 10-14V, trigger Delay 0.5-5s, pulse time is 1-100ms (default) and 1-500ms (setting).
The portable battery-operated SQ SW1 Spot Welder is widely used in electronic products, power banks, electric vehicles, model airplanes, ship models, power tools, etc.
This compact spot welder is easy to carry and store, easy to operate, has high and low voltage warning, and OLED display.
SQ‑SW1 has adapted advanced spot welding technology, intelligent switching automatic/ manual working mode to meet different needs, and its outer body is sufficiently strong.
Using this spot welder, you need to arrange the battery as it does not come with the package. The recommended battery for this welder is a Lithium battery (3S 5000mAh minimum 60C) Car battery (12V 400-800CCA).
Pros
• Good quality compact and portable spot welder.
• Convenient to use, and you can install it quickly.
• Automatic/manual modes.
• Strong outer body.
• OLED (Organic Light-Emitting Display).
• Provision for a foot pedal.
Cons
• Costlier for hobbyists.
• Brand reliability is unknown.
• You have to pay extra cash to arrange the battery.
Best Mini Spot Welder
Kerpu Rechargeable Portable Spot Welder
Kerpu Rechargeable Portable Spot Welder is a compact, portable (1.79 pounds), budget spot welder suitable for DIY and creative projects.
This upgraded portable spot welder has its protection against over-charge, over-discharge, and over-temperature and a unique overheating protection device that automatically cuts power when any overheating happens.
Kerpu spot welder has six output grades or levels. The six gears can be adjusted cyclically, and each time you press it, it will have a different melting point, strength, and the advanced power management and software design will not return to zero or reset during work.
Kerpu is easy to operate, has both manual (adjustable) mode and an automatic mode, a dedicated button for using the modes, and is powered by a rechargeable lithium battery with 3.7-4.2 V, 6.7 Ah (6700 mAh).
The welder has a load capacity of approximately 400 A. it comes with a charging control module, charging the battery through a type-C interface, with a maximum input of 5V/2A, and the charging time is 3 hours.
If the temperature goes higher than 140ºF during the work, the spot welder automatically shuts the power off. It also automatically shuts off if it is idle for more than 8 minutes.
You can use this for 18650 and other cylindrical lithium batteries, nickel-metal hydride batteries, and cadmium nickel batteries.
You can also use this to weld iron, steel, stainless steel sheets with a thickness less than 0.2 mm/0.008 inch to other iron, steel, stainless steel metals.
The length of the welding pen is 16 inches, making it flexible and comfortable to use.
Pros
• Compact and weighs 1.79 pounds.
• Powered by a rechargeable lithium battery of 6,700 mAh.
• The maximum peak output current is 650A.
• 16 inches length welding pen.
• Under USD 100 spot welder.
• High-temperature protection system.
• 3-hour battery charging.
Cons
• Brand reliability is unknown.
• Limited for thickness less than 0.2 mm/0.008ʺ.
2nd Best Mini Spot Welder
TUNFOU Portable Spot Welder
TUNFOU Portable Spot Welder is a compact, portable (1.76 pounds), budget spot welder suitable for DIY and creative projects.
This battery-operated TUNFOU portable spot welder is powered by a rechargeable polymer lithium battery with a maximum output voltage of 4.2 V. The maximum peak output current is 650 A. The maximum designed current is 1000 A with a type-C charging port. The battery charging time is 3 hours.
This spot welder has built-in safety features including, overcurrent protection, low-voltage, overvoltage, and over-temperature.
It has an intelligent output current; all high current circuit layouts use infrared thermal imaging for optimizing the design and better share of the discharge current and designed with circuit protection to enable you to charge the spot welder safely.
This spot welder is designed to cut off when the temperature is higher than 60º C. The spot welding pens are easy to disassemble and assemble and have a length of 15.8 inches to meet most of your spot welding needs.
TUNFOU spot welder uses a single chip to precisely control the output current of the MOS (metal-oxide-semiconductor) tube and generates a high temperature at the welding point to make the nickel sheet weld firmly. The welder is capable of welding a thickness of 0.1 to 0.15 mm.
The outer body of the TUNFOU spot welder is made of aviation-grade aluminum alloy (makes it resistant to minor falls), and the spot welding pen is made of good quality copper.
Pros
• Compact and lightweight, weighing 1.76 pounds.
• Budget product, less than USD 75.
• Charging time 3 hours.
• Six selectable gears (levels).
• Manual and automatic mode.
• 15.8 inches pen.
• The outer body is made of aviation-grade aluminum alloy.
Cons
• Brand reliability is unknown.
• Limited recommended nickel thickness is 0.1 to 0.15 mm.
Spot Welder Buyers Guide
How to choose your spot welder?
We are giving you a few buying tips that may help to make the decision easy and simple.
If you are a DIY person using batteries in your project or your professional work involves working on circuits or connecting batteries, then you need a spot welding machine. You can also use the spot welder to join two thin metal parts or strips.
Principle of working of a spot welder:
If you connect a piece of metal to an electric source and put the switch on, the metal offers electrical resistance to the flow of current through it, and due to this, the metal becomes hot.
When you overlap two thin metal parts and pass current through them, the heat generated at the point of overlapping (due to the electrical resistance for the flow of current) is sufficient to fuse the two metal parts together.
The fusion of the two metal parts can be made better by using a force on the location. This is the principle of resistance welding and is used in most spot welders.
During the resistance welding process, the two metal workpieces are held between the copper electrodes, and weld current and pressure are applied through the electrodes. The thickness of the spot-welded metal can be 0.1 mm and more depending on the spot welder capacity.
Most spot welders have a simple design, and they are made for one function only.
What do you want to do with the spot welder?
The spot welder can do two jobs:
- Interconnecting two or more batteries with the help of a metal foil. A length of thin metal strip is placed on the terminal of two or more batteries, and then they are spot welded.
- Joining two thin overlapping metal strips or sheets with spot welding.
Some spot welders can do only one of the above jobs, and there are spot welders that can do both types of jobs.
Evaluate your DIY or professional projects and decide on the type of spot welder you want.
Buying Guide
Welding Thickness
The thickness range of most battery spot welders is limited to the range of 0.05 mm to 0.35 mm, which should be sufficient for most uses. Depending on the welder specification, the maximum limits that it can weld may be as little as 0.1mm.
Depending on your welding connections types and battery sizes, you must select the welder that copes with your project requirements.
Output Current
The sport welder output current is vital information in the specification that you need to consider before purchasing. The output current comes in a range; this range specifies how thin and thick material we can weld.
Choosing a spot welder that offers a wide range is always recommended to give us more flexibility and power for spot weld all sizes of wires on all kinds of batteries.
Typically, the most decent spot welder will provide an out current range of 50A to 800A going all the way to 50A to 1200A, which is sufficient for most applications.
Spot Welder Work Cycle
The work cycle is the time the spot welder can work before waiting for the cycle to refresh. Typically, battery spot welders come with a work cycle of about 20 pulses per minute, which is sufficient for performing several spot welds before waiting for the work cycle to refresh.
Compatible Batteries
Some spot welders are specifically designed for battery welding of types 18650, 14500, or other lithium batteries. However, some welders are limited to work with 18650 only.
You need to select the welder compatible with the batteries you intend to weld before making your choice.
Reach of the spot welding pen
Many spot welders have provision for a mobile spot welder pen. The reach of the spot welder pen indicates the length of the cable attached to the pen, and the cable connects the pen with the spot welder machine.
Portability
You have compact battery-operated spot welders that are small enough to carry in your pocket and other spot welders that connect to the main and are light enough to carry around. Keep this aspect in your mind when you make your selection.
Quality of welding and brand reputation
The brand of many spot welders may be unknown to you. The user reviews can be helpful and guide you. Please go through our above review, then to the user reviews, make a list of your queries and get it clarified from the seller.
Warranty
This is another important factor. Please study and understand the warranty period and warranty clauses clearly. Ask for clarifications if you are in doubt.
Budget
You can find battery spot welders ranging from under USD 100 to USD 500 or more. Spot welders costing under USD 300 can be suitable for DIY enthusiasts and metal art hobbyists. However, if you have plans to convert your hobby into a profession, you may have to do more homework before making your decision.
Frequently asked questions
Where to buy a spot welder?
Amazon is one good place for online purchases. You have a wide selection to make your choice, and the user reviews help you understand the product better. You can also ask your questions about the product and clarify from the seller, and you can directly talk to the seller to clarify your doubts.
How can I check the spot welding quality?
The peeling test is the best for checking the spot welding quality, but this is a destructive test and hence does it on sample pieces. Try to pull and peel the two spot-welded strips apart using your hands, tongs, or any other tools, and you can judge the quality of spot welding yourself.
Our final verdict
We have reviewed six popular battery spot welders on the market and provided you with a helpful guide to assist you in making a wise choice.
Each welder is reviewed in detail to help you understand the machine, and finally, we discussed a few buying tips for purchasing a spot welder and ended with few frequently asked questions.
Equip yourself with the proper spot welder that matches your demands and your project requirements, and you are set to go.
Hopefully, this article gave you sufficient information and will help you purchase a good quality spot welder within your budget.
