To assemble the simplest battery-powered circuit, we have to resort to various tricks so that the wires fit snugly against the poles of the battery itself. Someone manages with electrical tape and scotch tape, someone comes up with various kinds of pressure devices. But in this case, the contact will be imperfect, which ultimately affects the performance of the assembled circuit. Often, contact disappears or it turns out to be loose, and the device works intermittently. To avoid this, it is best to simply solder the wires to the poles. In this article, we will tell you how to solder the wires to the battery so that the contact is perfect.

The simplest example of a device

The simplest battery powered device is an ordinary electromagnet. On his example, we will check the performance of our student soldering. We take an ordinary nail, for example, weaving, wind a copper wire around it in dense rows. We insulate the turns from above with electrical tape. The electromagnet is ready. Now all that remains is to power the device from the battery.

Of course, you can simply press down on the wiring from each end of the battery and the device will already start working. But it is inconvenient to use it. Therefore, it is best to keep the wires in constant contact with the power source. This can be done by adding an ordinary switch (toggle switch) to the network and soldering the wires to the battery poles directly. The device will become more reliable, it will be more convenient for them to use, and if it is not needed it can always be turned off by opening the circuit with a switch so that the battery does not run out. But how do you solder the wires to the battery so they don't fall off after five minutes of using the device?

Tools and consumables required for soldering

In order to carry out reliable soldering of wires to the poles of the battery, you need the necessary set of tools. Since soldering a wire to a battery is a more difficult task than just soldering a pair of copper wires together, we will do everything exactly according to the instructions below. In the meantime, let's prepare everything you need:

1. An ordinary household hand-held soldering iron. They will also solder the wires to the battery poles.
2. Sandpaper or a file to remove slag and carbon deposits from the soldering iron tip.
3. Sharp knife. They will strip the wires if they are braided.
4. Flux or rosin. Which soldering flux is suitable in this case? Let's not break our brains here, let's take a simple soldering acid, it is sold in any store that sells radio goods. Well, rosin, even in color and shade, is often different, but its properties are always the same.
5. Brush for applying flux.
6. Solder. It can be purchased in the same place as the flux.

We solder the wires to a regular battery

So how do you solder the wires to the 1.5V battery? This task is not difficult, if everything you need is already at hand. We act according to the following instructions:

Everything, the wires are qualitatively soldered to the battery.

We solder the wires to the crown

How to solder a wire to a Krona battery? Here, soldering is carried out in almost the same way as in the case of a conventional battery. The only difference is that in the "Krona" 9V battery, plus and minus are located side by side on one upper side of the battery. The nuances are as follows:

1. In the case of the flux, we treat the "Crown" contacts with acid from opposite sides. There we will carry out the soldering of the wires.
2. In the case of rosin, it will be necessary to tin the contacts of "Krona" and also from opposite sides. Why from the opposite? Because in this case, the risk of a short circuit between the wires is practically reduced to zero.
3. The "Krona" 9V battery has contacts (poles) that are very inconvenient for soldering. At the top, they open in breadth, and therefore, for high-quality tinning and soldering from the side of such a contact, it is necessary that the tip of the soldering iron be narrower or sharper.

In general, the whole process is similar to the previous one. We process the contacts and the edges of the wires with acid (or tin in the case of rosin), press the wires to the contacts, take a little solder with a soldering iron and solder. The process is complete.

Batteries, rectangular, 4.5 V

It is even easier to solder wires to such batteries. They have flat folding contacts that can be tinned with ease. And soldering to them is easier and faster. The main thing is not to move the wiring during the soldering process. Otherwise, they will simply come off.

Here you can not hold the wire at all, but wind it around the plane of the contact strip. And then, having typed the tin with a soldering iron, solder.

Battery type batteries

It is better not to solder the batteries-accumulators, but to make a special container for them, in which the contacts of the elements will be in close contact with the pole contacts of the container. The material of batteries-accumulators consists of alloys, which amenable to soldering even worse than conventional lithium. But if you really itch, then soldering is carried out, as in the case of a conventional 1.5 V battery, just use a flux, not rosin. Plus, soldering should be done as quickly as possible, keeping the soldering iron touching the poles to a minimum, since such batteries are afraid of overheating.

Conclusion

Of the two options - rosin or flux - it is better to choose the flux. It will provide soldering with greater durability and reliability. Such soldering will not fall off even if the device is used very often. The only caveat is that acid vapors released during soldering are very harmful, therefore it is not recommended to inhale them, and after the procedure, you should thoroughly wash your hands.

When working with mobile household devices or a special tool with a built-in power source, there is often a need to solder the wire to the battery.

Before proceeding with this seemingly simple procedure, you should carefully prepare, which guarantees a reliable and high-quality connection at the end of the work.

Both the alkaline or lithium battery itself and the connecting conductor that is soldered to it need preparation.

These procedures also include the preparation of the required consumable, including such important components as solder, rosin and flux mixture.

The most difficult and crucial moment of the upcoming work is stripping the battery terminal, to which the connecting wire is supposed to be soldered. The specified procedure may seem simple only for those who have never tried to do this.

The problem in this case is that the aluminum contacts of power supplies (finger or other type - it doesn't matter) are subject to oxidation and are constantly covered with a coating that interferes with soldering.

To clean them and then isolate them from air, you will need:

• sandpaper;
• a medical scalpel or a well-sharpened knife;
• low-melting solder and neutral flux additive;
• not very "powerful" soldering iron (no more than 25 watts).

After all these components are prepared, the following operations must be performed. First, you need to carefully clean the place of the proposed soldering, using first a scalpel or knife, and then a fine emery cloth (it will ensure better removal of the oxide film from the contact zone).

In parallel with this, the bare part of the soldered wire must undergo the same stripping.

Immediately after preparation, you should proceed to the protective treatment of the terminals of a finger or any other battery.

Flux treatment

To prevent further oxidation of the contact, the surface of the battery, free of plaque, should be immediately treated with a flux mixture made on the basis of ordinary rosin.

If, for example, there are no greasy oil stains on the contacts of the phone's battery, you just need to wipe them with a soft flannel dipped in ammonia.

After that, it will be necessary to warm up the soldering iron well, solder the contact area with a few quick touches. This completes the preparation for soldering.

Soldering process

After each of the parts to be connected is cleaned and treated with flux, proceed to direct soldering of the wire to the contact area of ​​the battery.

For this final procedure, you can use the same 25-watt soldering iron that was used to prepare the battery terminals from NI or CD.

A low-melting compound should be chosen as a solder, and a rosin-based flux should be used for its good spreading.

The final soldering procedure should take no more than 3 seconds. This applies to any type of battery (both NI and CD).

The most important thing is to prevent overheating of the terminal part of the element, as a result of which it can be thoroughly damaged. The possibility of its complete destruction (rupture) during the soldering process is also not excluded.

When considering how to solder a wire and a battery, it should be noted that this situation is much more common than it seems. First of all, this applies to special construction tools (if it is necessary to solder the batteries of a screwdriver, for example).

It is not uncommon for the built-in power supply of the tool used to be completely destroyed for some reason, and there is nothing to replace this screwdriver with. In this situation, the conductors supplying the device are soldered to a spare battery rated for the same voltage.

This technique can be used when you just need to solder two batteries together.

It should be noted that instead of soldering in production, spot welding is used for batteries. But not everyone has an apparatus for this type of connection, while a soldering iron is a more common device. Therefore, soldering at home comes to the rescue.

Batteries and accumulators

When powering radio equipment from batteries and accumulators, it is useful to know the common schemes for connecting batteries and accumulators. The fact is that each type of battery has a permissible discharge current.

The discharge current is the most optimal value of the current that is consumed by the battery. If you consume a current exceeding the discharge current from the battery, then this battery will not last for a long time, it will not be able to fully give up its calculated power.

Probably, they noticed that for electromechanical watches, “finger” (AA format) or “pinky” (AAA format) batteries are used, and for a portable lamp flashlight, there are more batteries (format R14 or R20), which are capable of delivering significant current and have a large capacity. Battery size matters!

Sometimes it is required to provide battery power to an instrument that draws significant current, but standard batteries (for example R20, R14) cannot provide the required current, it is higher than the discharge current for them. What to do in this case?

The answer is simple!

It is necessary to take several batteries of the same type and connect them to a battery.

So, for example, if it is necessary to provide a significant current for the device, a parallel connection of batteries is used. In this case, the total voltage of the composite battery will be equal to the voltage of one battery, and the discharge current will be as many times as there are batteries used.

The figure shows a composite battery of three 1.5 volt batteries G1, G2, G3. If we take into account that the average value of the discharge current for 1 AA battery is 7-7.5 mA (with a load resistance of 200 Ohm), then the discharge current of the composite battery will be 3 * 7.5 = 22.5 mA. So, you have to take the quantity.

It happens that it is necessary to provide a voltage of 4.5 - 6 volts, using 1.5 volt batteries. In this case, you need to connect the batteries in series, as in the figure.

The discharge current of such a composite battery will be the value for one cell, and the total voltage will be equal to the sum of the voltages of the three batteries. For three AA (finger-type) cells, the discharge current will be 7-7.5 mA (with a 200 Ohm load resistance), and the total voltage will be 4.5 Volts.

In the life of every "radio killer" there is a moment when you need to weld several lithium batteries together - either when repairing a laptop battery that has died of age, or when assembling power for the next craft. Soldering "lithium" with a 60-watt soldering iron is inconvenient and scary - you will overheat a little - and you have a smoke grenade in your hands, which is useless to extinguish with water.

Collective experience offers two options - either go to the trash heap in search of an old microwave oven, knock it out and get a transformer, or spend a lot of money.

For the sake of several welds a year, I did not want to look for a transformer, saw it and rewind it at all. I wanted to find an ultra-cheap and ultra-simple way to weld batteries with electric current.

A powerful low-voltage DC power supply available to everyone - this is an ordinary used device. Battery from the car. I bet that you already have it somewhere in the closet, or that your neighbor can find it.

I suggest - the best way to get an old battery for free is

wait for frost. Go to the poor fellow who does not start the car - he will soon run to the store for a new fresh battery, and give the old one to you just like that. In the cold, the old lead battery may not work well, but after charging the house in the warmth it will reach its full capacity.

To weld batteries with current from a battery, we will need to deliver current in short pulses in a matter of milliseconds - otherwise we will not get welding, but burning holes in the metal. The cheapest and most affordable way to switch the current of a 12-volt battery is an electromechanical relay (solenoid).

The problem is that conventional 12 volt automotive relays are rated for a maximum of 100 amperes, and the short circuit currents during welding are many times higher. There is a risk that the relay armature will simply be welded on. And then, in the vastness of Aliexpress, I came across a motorcycle starter relay. I thought that if these relays withstand the starter current, and many thousands of times, then it will work for my purposes. This video finally convinced me, where the author is testing a similar relay:

My relay was bought for 253 rubles and reached Moscow in less than 20 days. Relay characteristics from the seller's website:

• Designed for motorcycles with 110 or 125 cc engine
• Rated current - 100 amperes for up to 30 seconds
• Winding excitation current - 3 amperes
• Designed for 50 thousand cycles
• Weight - 156 grams

The relay arrived in a neat cardboard box and upon unpacking gave off a wild stench of Chinese rubber. The culprit is a rubber casing on top of a metal case, the smell has not disappeared for a day.

The unit pleased with the quality - two copper-plated threaded connections are brought out under the contacts, all the wires are filled with a compound for waterproofing.

Hastily assembled a "test stand", closed the relay contacts manually. I used a single-core wire, with a cross section of 4 squares; I fixed the stripped terminals with a terminal block. For safety reasons, I supplied one of the terminals to the battery with a "safety loop" - if the relay armature decided to burn and arrange a short circuit, I would have had time to pull off the terminal from the battery for this rope:

Tests have shown that the machine works for a solid five. The armature knocks very loudly, and the electrodes give clear flashes; the relay does not burn. In order not to waste a nickel strip and not to practice on dangerous lithium, I tormented the blade of a clerical knife. In the photo you can see several high-quality dots and a few overexposed ones:

Overexposed dots are also visible on the inside of the blade:

First, he piled up a simple circuit on a powerful transistor, but quickly remembered that the solenoid in the relay wants to eat as much as 3 amperes. I rummaged in the box and found an IRF3205 MOSFET transistor instead and sketched a simple circuit with it:

The circuit is quite simple - in fact, a MOSFET, two resistors - for 1K and 10K, and a diode that protects the circuit from the current induced by the solenoid when the relay is de-energized.

First, we try the circuit on the foil (with joyful clicks, it burns holes through and through through several layers), then we take out the nickel tape from the storage box to connect the battery assemblies. We briefly press the button, we get a loud flash, and we consider the burnt hole. The notebook also got it - not only nickel burned, but also a couple of sheets under it :)

Even a tape welded with two points cannot be divided by hand.

Obviously, the scheme works, it's up to fine-tuning the "shutter speed and exposure". If you believe the experiments with the oscilloscope of the same friend from YouTube, from whom I spied on the idea with the starter relay, then it takes about 21ms to break the armature - from this time we will dance.

YouTube user AvE tests the rate of fire of the starter relay versus SSR Fotek on an oscilloscope

We supplement the scheme - instead of manually pressing the button, we will entrust the countdown of milliseconds to Arduin. We will need:

• Arduino itself - Nano, ProMini or Pro Micro will do,
• Sharp PC817 optocoupler with a 220 Ohm current-limiting resistor - to galvanically isolate the Arduino and the relay,
• A voltage-reducing module, for example XM1584, to turn 12 volts from the battery into 5 volts safe for Arduina
• we also need 1K and 10K resistors, a 10K potentiometer, some kind of diode and any buzzer.
• And finally, we will need a nickel tape, which is used to weld batteries.

Putting together our simple scheme. We connect the release button to the D11 pin of the Arduino, pulling it to “ground” through a 10K resistor. MOSFET to pin D10, buzzer to D9. I connected the potentiometer with the extreme contacts to the VCC and GND pins, and with the middle ones to the A3 pin of the Arduino. If you wish, you can connect a bright signal LED to the D12 pin.

Fill the Arduino with some tricky code:

Const int buttonPin = 11; // Shutter button const int ledPin = 12; // Pin with signal LED const int triggerPin = 10; // MOSFET with relay const int buzzerPin = 9; // Beeper const int analogPin = A3; // Variable resistor 10K for setting the pulse length // Declare variables: int WeldingNow = LOW; int buttonState; int lastButtonState = LOW; unsigned long lastDebounceTime = 0; unsigned long debounceDelay = 50; // minimum time in ms to wait before triggering. Made to prevent false alarms when the release button contacts bounce int sensorValue = 0; // read the value set on the potentiometer to this variable ... int weldingTime = 0; // ... and based on it we set the delay void setup () (pinMode (analogPin, INPUT); pinMode (buttonPin, INPUT); pinMode (ledPin, OUTPUT); pinMode (triggerPin, OUTPUT); pinMode (buzzerPin, OUTPUT) ; digitalWrite (ledPin, LOW); digitalWrite (triggerPin, LOW); digitalWrite (buzzerPin, LOW); Serial.begin (9600);) void loop () (sensorValue = analogRead (analogPin); // read the value set on the potentiometer weldingTime = map (sensorValue, 0, 1023, 15, 255); // convert it to milliseconds in the range from 15 to 255 Serial.print ("Analog pot reads ="); Serial.print (sensorValue); Serial.print ( "\ t so we will weld for ="); Serial.print (weldingTime); Serial.println ("ms."); // To prevent false triggering of the button, first make sure that it is held down for at least 50ms before starting welding: int reading = digitalRead (buttonPin); if (reading! = lastButtonState) (lastDebounceTime = millis ();) if ((millis () - lastDebounceTime)> debounceDelay) (if (reading! = buttonState) (buttonState = reading; if (buttonState == HIGH) (WeldingNow =! WeldingNow;))) // If the command is received, then start: if (WeldingNow == HIGH) (Serial.println ("== Welding starts now! =="); delay (1000); // Output three short and one long beeps to the speaker: int cnt = 1; while (cnt<= 3) { playTone(1915, 150); // другие ноты на выбор: 1915, 1700, 1519, 1432, 1275, 1136, 1014, 956 delay(500); cnt++; } playTone(956, 300); delay(1); // И сразу после последнего писка приоткрываем MOSFET на нужное количество миллисекунд: digitalWrite(ledPin, HIGH); digitalWrite(triggerPin, HIGH); delay(weldingTime); digitalWrite(triggerPin, LOW); digitalWrite(ledPin, LOW); Serial.println("== Welding ended! =="); delay(1000); // И всё по-новой: WeldingNow = LOW; } else { digitalWrite(ledPin, LOW); digitalWrite(triggerPin, LOW); digitalWrite(buzzerPin, LOW); } lastButtonState = reading; } // В эту функцию вынесен код, обслуживающий пищалку: void playTone(int tone, int duration) { digitalWrite(ledPin, HIGH); for (long i = 0; i < duration * 1000L; i += tone * 2) { digitalWrite(buzzerPin, HIGH); delayMicroseconds(tone); digitalWrite(buzzerPin, LOW); delayMicroseconds(tone); } digitalWrite(ledPin, LOW); }
Then we connect to Arduin using the Serial monitor and turn the potentiometer to set the length of the welding pulse. I empirically selected the length of 25 milliseconds, but in your case the delay may be different.

By pressing the release button, the Arduino will squeak several times, after which it will turn on the relay for a moment. You will need to lime a small amount of tape before you can find the optimal pulse length to weld and not burn the hole through.

The result is a simple, artless welding machine that is easy to disassemble:

A few important words about safety:

• When welding, microscopic metal spatter can fly to the sides. Do not show off, wear safety glasses, they cost three pennies.
• Despite the power, the relay can theoretically "burn" - the relay armature will melt to the point of contact and will not be able to return back. You will get a short circuit and a quick warm-up of the wires. Consider in advance how you will pull off the terminal from the battery in such a situation.
• You can get different degrees of welding depending on the battery charge. To avoid surprises, adjust the welding pulse length on a fully charged battery.
• Think in advance what you will do if you pierce the lithium 18650 battery - how you will grab the incandescent element and where you will throw it to burn out. Most likely, this will not happen for you, but with video the consequences of spontaneous combustion of 18650, it is better to familiarize yourself in advance. At a minimum, prepare a metal bucket with a lid.
• Monitor the charge of your car battery, do not allow it to discharge strongly (below 11 volts). This is not useful for the battery, and you will not help out a neighbor who urgently needs to "light" the car in winter.