How to charge a car battery charger from a laptop

Hello! I decided to create this post, because it may be able to help someone in a frequent occasion when the battery is fully discharged and there are no fixed assets for its “revival”. For example, the charger for the battery, or a pair of human filled shower, ready with a smile and joy to push your typewriter so that in the future, the gene could work out his. =)

I came across such a problem myself, but I was lucky to find an interesting video on a popular video hosting, with a detailed description of the battery charging scheme at home, with the help of a charger from a laptop and a car lamp H5, which rescued me three times.

You can read a deeper, turning to Yutub on the roller. I have been used: Charger from HP Laptop (19 V, 4.74 A) and Car Lamp H5 (90 W). Connection diagram: “minus” charger is connected to a “minus” acb via lamp, and plus, directly from the charger to the “plus” battery.

Here’s how it looked with me. In my own experience, I can say that 6-9 hours grabs quite. precisely, 6 hours so that it was possible to at least twist the starter normally, and 9 hours already boiled the battery and the “peephole” was green.

I have from the previous owner of the Akb “Tyumen Bear”, this year will be 4 years old. Really, he can be glad, because there were a few moments when I thought already. But he got out. And in frosts under.25 calves the charge, even if the week did not fit to the car at all, or a month started a couple of times. over, considering that I have a “Barachlit” generator and its repair will also need to do, but so far everything was exactly.

charge, battery, charger, laptop

IMPORTANT! Polarity observe anything!

Significant comment that I will allocate: “The lamp does not limit, but determines the current of the charge, from its resistance and the current depends, the voltage is always there 20 V, at least put some lamp, but the more powerful lamp. the higher the current, accordingly faster the battery. without a lamp. BP just to burn maybe, It turns out the KZ, Akb automotive resistance to the insignificant current will be a giant. the fuse or the BP itself burns “

The complexity of the design of lithium-ion batteries for laptops

The first thought that comes to mind. why not take with you a similar battery about the supply? On the one hand, quite a logical decision. But if you open the battery compartment of any laptop, it is found that not everything is so simple as it seems. We will have to work very hard to remove the laptop battery from the compartment “native” and insert a new battery in it. over, the PC body, and the battery compartment is made of light plastics. With a frequent shift and installing a new battery, they can easily break.

If you carefully examine the connector of such a battery, it is found on it at least 7-9 output contacts, unlike the automotive battery, where the contacts are known, only two: minus and positive. All these findings control the charge-discharge process of each “bank” inside the battery compartment. There is also a fee where the entire electronic system for protecting lithium-ion elements from overheating and deep discharge is programmed.

This fee for security should be installed in the battery compartment of any portable device with lithium-ion elements. Without it, they can easily explode. In “emergency” situations, the controller on the board breaks the electrical circuit and blocks current flow.

As you can see, replacing the battery with a laptop and charging it directly, from a outer battery, is a difficult task. However, if there is no other exit, then you can try to implement several ways that offer electronics lovers.

Do not forget about checking

To check again you should use the tester. Connect the tester to the power supply contacts, poke them into battery contacts. If the power supply voltage is reduced on the power supply unit to the value approximate to the voltage of the battery, then we can talk about the incorrect charge process.

Checking laptop battery testers

We reviewed the effective and affordable charge principles without the computer itself. But it is important to remember. such measures are available only for reliable batteries of famous manufacturers. Often, Chinese analogues are not equipped with appropriate protection, so it is not worth the risk.

We hope that in your life will not arise such unpleasant situations with the need for urgent charge without a laptop. Although if necessary, you can take advantage of our recommendations. the most reliable, and safe approach, proven in practice.

The optimal option for frequent and long-term business trips and trips. to make bets on the model of computers with a long charge, enough battery with a battery. But if necessary, buy and take spare batteries with you. in most cases it is enough to carry out on the road for 10 hours, remaining in touch, solving your household or working tasks if necessary.

How to charge a car battery charging from a laptop? If you do not even do it

Often you can hear the question how to charge a car battery charging from a laptop. After all, it is not always possible to use fixtures to bring the battery to normal. And put it enough just. Under some conditions, even the best battery can be discharged. So what to do if you are far from the charger. This may occur under different circumstances. You went, for example, to the cottage or delayed visiting.

At the same time, the options will start the car, there is no pusher. Perhaps you have no workforce, or there is an automatic box. In any case, you will have to invent, how nevertheless start the car.

How to charge a car battery charging from a laptop? Actually do it is not difficult. Enough to attach hands. Attention! To charge the battery in this way, you will have to collect a fairly simple electrical circuit. If you are not sure in your skills, it is better not to try to do it. In this case, a permanent current will be used for charging. Therefore, it is important to keep track of the condition of the battery.

A relear may result in loss of battery of its properties or even to an explosion. Before starting the charging process, be sure to unscrew the tubes from cans. To compile the simplest charging, you will need:

Charging from laptops most often produce a voltage of 19-20 V, the current of current in them is about 5 A, the power of 80 W. An ordinary halogen light bulb will fit perfectly here. Note that what it is more powerful, the current current will be higher.

The device assembly occurs as follows. Connect wires to the charger outputs. Light bulb connects to the plus break. Wires should be attached to the battery terminals, while observe the polarity. If everything is assembled correctly, the light bulb should light up. Periodically check the voltage on the terminals. When it comes up to 13.5 V, the battery will be ready to use. Usually, the battery is 100 hours discharged to zero. If the battery is not discharged, then in order to make the car will be enough 2 hours.

If there is no charger from a laptop, then in principle you can use the power supply from any computer. But there are some nuances that do not allow using this device as a full charge. The fact is that the voltage issued by the BP (power supply unit) is 12 V, while for a full charge of the car battery required 14. Thus, you can only charge the battery with a block by 30-40%. But this is quite enough to start a good car. Further charging from the generator will go, well, or you will reach the place where there is quite normal charging.

When drawing up such a device, be extremely attentive. The system does not have a galvanic junction that threatens defeat the current. Therefore, turn on the device to the network only after the final assembly. During his work, do not touch the uninsulated sections of the wire. For assembly you need:

The device is assembled as follows. To the fork joined wires. The minus wire is immediately attached to the corresponding battery terminal. The advantage is divided into 3 equal parts. Diodes and light bulbs are consistently connected in the gaps. For assembly, diodes are suitable from the old energy-saving light bulb. If used, then for the full battery charging required about 15 hours.

When installing two charging time decreases by 2 times. Further increase in the number of diodes will only lead to greater power consumption. Connect the collected charging to the network. Just follow the battery do not bother.

It is not always possible to collect a charger, even from charged materials. Therefore, finally, a few tips, what to do if the battery does not turn the starter:

  • Always have wires for cigaretteing in the trunk. The order of connection is the following, first connect plus to the discharged battery, then another end of the wire to the output of the charged battery. The main wire is connected to the minus terminal of the donor, the second crocodile is attached to any part of the body of your car. Next, create a working machine and give it to work for a few minutes. If everything is done correctly, then your car will start. Read more Read the article “How to contact the car from another machine”;
  • If your battery turns a little starter, but this is not enough for the plant to the cold, then ask the battery at the neighbor. Start and warm your car. After which you will probably get started on your battery.

Conclusion. As a rule, problems with the battery happen suddenly. Therefore, motorists are not ready for such a turn of events. In this case, it is not bad to know how to charge the car battery charging from the laptop. After all, this problem can take away a lot of time and nerves. And to solve the traditional way, that is, the use of factory charging, it is not always possible.

How to charge a laptop battery outside?

There are many adapters that can be used to charge laptop batteries. External adapters are not connected to a laptop. Battery Charges Outside Laptop. In this case, the battery is removed from the laptop and connects to the terminals of the external charger. Then the charger is connected to the power supply, and the battery begins to charge. When charging is completed, the battery is inserted back back into the laptop.

When choosing an external charge device for a laptop, caution should be taken as they are intended for certain brands and models. Thus, you must check the one that matches the specifications of your laptop. At the same time, the spare battery can be conveniently charged without having to turn off the laptop.

Directly from the power supply

So we got to the most unsafe method, but it is most fully answering the topic of articles and is ideal for extreme lovers. To work, we need a multimeter, a power source, a current-limiting resistor. Multimeter will adapt any capable of measuring constant voltages of up to 20 V.

Power Supply. A good option. a regular charger from a laptop, whose battery we are going to charge. As an alternative. any stabilized energy source with output voltage at 1-5 above the output voltage of a fully charged battery capable of to give current into the load at least 2 A. The operating voltage is usually indicated on the battery case.

For the battery shown in the photo above, you will need a power supply with output voltage 12-16 V. If we use a power supply for a laptop (optional. ours), then its output voltage and current can be found on the housing.

Now the current-limiting resistor. Its nominal and power will depend on the output voltages of the battery and power supply. Suppose we have an AKB by 11.1 V, and the unit is 12 V. Charge will be the initial current of 1.5 A. It’s a bit, but most safe for the battery, although the process will take more time. Calculate the voltage that should fall on the resistor. At the same time, the amount of battery voltage take 10.2 V (completely discharged). 12. 10.2 = 1.8 V. According to the formula Oka, we calculate the resistance of the resistor on the basis of the charging current of 1.5 A. R = U: i = 1.8: 1,5 = 1.2 ohms. It remains to calculate the power dissipated on the resistor. P = u x i = 1.8 x 1,4 = 2.7 W.

Such a resistor can be removed from the pulsed power supply units of televisions, but if there is a problem with this, it will replace the high-light automotive lamp with a capacity of 45-55 W.

It remains to collect the scheme and start charging, but first look at the laptop power unit connector. It can be two- or three-contact. In a two-contact, having a view of the tube, internal contact is “plus”, external. “minus”.

Repair specialist, electrical equipment and industrial electronics.

Important! It is extremely rare, but there are power supplies that have a plug connected on the contrary. outside “plus”, inside “minus”. Therefore, to accurately determine the polarity, we use a tester in a voltmeter mode or process with information applied to the adapter housing. Otherwise we risk burning the battery controller.

Pinout plug is often indicated on the adapter housing

Now there are three-contact plugs for connecting electrical blocks. They have the same, but inside the tube there will be a third contact in the form of a thin pin. This is an information conclusion that indicates the laptop that the power supply is connected to it and voltages are connected to it.

And now let’s turn to the diagram that we have to collect. It is relatively simple, the main thing is not to confuse the polarity of the BP connection to the battery.

Scheme that allows you to charge the battery without a laptop

So, with the help of a multimeter or by the battery scheme, we find the main power tires and their polarity. If the battery has a control entry, we find out where he and what needs to be filed (see. higher).

Connect to the plot of the block two wires. If the BP is regular, it will be convenient to use the appropriate outlet.

If there are no sockets, you can connect more easily. inside the plug tube insert the wire, which will be plus, wrap around the tube minus and fasten all the tape.

Plus wire through the quenching resistor (lamp) connect to the positive input / battery output, minus. to minus. Carefully follow the polarity.

In parallel to battery power terminals (no power supply!) Connect a voltmeter (tester). Turn on the power supply to the network, start charging, constantly controlling the voltage and temperature of the block of the battery. Voltage will begin to gradually increase, approaching the nominal battery voltage. As soon as it exceeds the nominal value of 0.3-0.4 V, the charging stop.

Let the battery do not gain 100% charge, but if the process does not stop, then the “harsh” types of controllers can stand on blocking, to exit from which without special equipment and knowledge will be impossible. Turn off the BP from the network, disassemble the scheme, and we can assume that the battery is charged.

Important! If the temperature of the battery will increase noticeably, charging immediately stop. Otherwise, nutrition elements can light up or explode. Here without a fire extinguisher and, perhaps, ambulance can not do.

How to charge a laptop battery without a laptop

Attention! This article is purely familiarized, in no way attempt to implement the actions below if you do not have knowledge in electronics or electrician, and also do not have the appropriate equipment. Any, even the slightest error can provoke the failure of the battery, and, more worse, the explosion and fire.

In fact, the need to charge the laptop battery by any non-standard method may occur in extremely rare cases. In addition, such an idea is contrary to the rules of operation of laptop batteries. Therefore, if you have a question how to charge a laptop battery without a laptop, we recommend that you first think about the possible consequences described above.

Special devices

Years ago. Now on Aliexpress and other similar services you can find chargers that manufacturers are seen, suitable for all types of laptop batteries. Such devices are a set consisting of a power supply and wires to which various adapters are connected. And again it is worth noting, even such devices will not be able to use without appropriate knowledge in electrics or electronics.

How is the battery charge with non-standard methods

Previously, the controllers that are responsible for the uniform charge of the battery sections were placed in a laptop. But the situation has changed, and to make accumulators safer, manufacturers have transferred controllers to their housing. Due to this, the process of charging the battery laptop with non-standard ways has become less dangerous.

In order to charge the battery outside the laptop, you must do the steps described below.

Find the input and output battery terminals

Usually in all electronic household devices. these are extreme terminals that are indicated by signs plus and minus. But if there are no designations, make an inspection of extreme contacts using a voltmeter.

charge, battery, charger, laptop


Connect the voltmeter with the power supply contacts, and then stick them to the appropriate battery terminals. Make sure that the voltage level on the power supply block is reduced to the level close to the battery voltage. In this case, the charge occurs.

Check the controller

Make sure the controller protecting from recharging works correctly. To do this, leave the voltmeter connected throughout the charging process and periodically look at it. Ideally, the voltage should smoothly increase to one of the following values:

  • eight.4 volts for batteries with mark 7.4 V;
  • 12.6 volts for batteries marked 10.8 V;
  • sixteen.8 volts for batteries marked 14.8 V.

At the same time, if to achieve one of the listed indicators, the voltage will change dramatically to the power supply voltage, it means that everything is fine. But if it goes further to increase, the protection does not work, and it is necessary to urgently interrupt the connection.

Types of laptop batteries

To figure out how to charge the laptop battery correctly, you must first determine its type. Modern batteries are such types:

  • Nickel-Metal Hydride (NI-MH). Alkaline power supplies used for power supply toys, electronics, lamps and other household appliances. Differ in relatively small electrical capacity, so no longer used for a complete set of laptops.
  • Nickel Cadmium (NI-CD). The main sphere of using the portable battery of this type. the power of the manual power tool. Today such batteries are practically not used in laptops.
  • Lithium-ionic (Li-Ion). The most common type of batteries used now in most laptops. Pluses Li-Ion batteries. low weight and sizes, high durability. They are designed for about 1000 working cycles and do not require maintenance. Another advantage consists in a small self-discharge of such batteries. This makes them well-appropriate for power supply devices designed for long-term offline work, including laptops.

Battery malfunctions

Next frequent culprit of the problem under consideration. directly laptop battery. Modern lithium-ion components have much better characteristics than those installed 15-20 years ago, but the price has become increased technical complexity and, as a result, the increase in the probability of breakage. Each battery has its own chip, which is responsible for the charging process and energy returns to the main device. it can fail due to non-accurate circulation or voltage drops.

It is also impossible to exclude banal wear. alas, but the batteries are also not eternal and have a certain service life, usually measured in charging and discharge cycles. Highly worn power supply can show symptoms like the considered, so if the laptop is quite old (more than 7 years in use) and the battery did not change in it, it should be replaced to solve it. It is also worth entering suspected breakdown. alas, but in most cases the repair is economically inexpedient.