Is a procedure that every motorist should be able to perform. The fact is that not a single battery can work forever, and its discharge or failure can cause serious inconvenience to the car owner. Therefore, in this article we propose to find out how to check the battery with your own hands, and what you need to know about this procedure.

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Visual check

To begin with, we propose to learn how to make a visual diagnosis of the device's state of operability at home. This check should be done regularly every time you open the hood. As you know, during the entire service life, dust and dirt, as well as moisture, accumulate on the battery case, especially since when the device boils, part of the working solution may come out of the cans. All these nuances affect the formation of the battery self-discharge current.

In addition, if the terminals of the device are oxidized, then another part of the current will go to leakage, and this, in turn, can cause a complete discharge of the device. So if you do not have time to timely detect the problem and eliminate it, it can develop into sulfation, that is, the destruction of the plates located inside the structure. And this, in turn, will reduce the battery life.

In order to prevent a quick failure of the battery, it is necessary to remove the drips of the working fluid; for this, water mixed with soda is used (1 tsp soda per glass of liquid). conclusions car battery you should also periodically clean it from oxidation, for this you can use a regular tooth or iron construction brush, sandpaper is also suitable. But keep in mind that you cannot be very diligent when cleaning, since you can remove the working surface of the terminals. Also, do not forget about checking the condition of the device case for cracks. As practice shows, damage to the case is usually formed as a result of exposure to vibrations that appear when the device is poorly fixed.

Electrolyte volume diagnostics

In addition, it is necessary to test the volume of the working fluid solution in the car battery; this operation can be performed directly on the car. This procedure should be followed on all serviceable batteries. Testing the volume of solution in jars is done using a tube - it would be ideal if the liquid covers all the plates and its level is about 1 cm above them.

For verification, a special level gauge tube is used - in fact, this is an ordinary tube on which graduations are marked, measured in millimeters. For testing, one end of the device should be lowered into the opening of the can, the tube is lowered until it touches the separator mesh, while the other part of it must be pinched with your finger. Ultimately, the fluid level in the tube will show the total fluid volume in the cans of the structure. If the volume is too small, then there is a possibility that the electrolyte will boil away, so distilled water will need to be added to the system.

How to check battery density?

You can also test the density of liquid in cans, for this you need a special analyzer - a hydrometer.

To diagnose batteries in this way, you need to do the following:

Open the hood of the car, disconnect the power terminals from the battery.
Unscrew all cans (the procedure is performed only on serviced batteries).
Install one end of the hydrometer in a jar, and then, using a pear, take the electrolyte solution. There must be enough liquid in the device so that its float can float normally.
Test results should be read on the scale of the testing device, while taking into account that the readings largely depend on the air temperature.

If the ambient temperature is around 20-30 degrees, the results will be the most accurate. In the event that the temperature does not correspond to this range, then it will also be necessary to add or subtract corrections to the readings obtained, they are detailed in the table. In new batteries, the density is about 1.27 g / cm3. If the diagnostic results showed about 1.22 g / cm3, this indicates that the device is discharged by 30%, but, of course, the value of the outside temperature should also be taken into account. The lower the air temperature, the faster the car battery will discharge.

How to check the voltage parameter?

To check the voltage level of a car battery, you will need a special device - a tester, it can be a voltmeter or a multimeter.

To diagnose the voltage value, do the following:

First, the tester must be configured to operate in constant voltage mode, and the maximum range must be set.
The negative terminal of the tester (black) must be connected to the negative terminal of the battery.
The positive probe (respectively, red) is connected to the battery positive.

As a result, readings should appear on the tester display - if the battery works in normal mode, then the values \u200b\u200bobtained as a result of diagnostics must be at least 12.6 volts. If the test showed less results, then we can conclude that the device's charge has dropped significantly, and more than half. In this case, the most the best option there will be a control and training cycle.

If you do not complete the CTZ in time, then the problem can lead to sulfation and, accordingly, shedding of the plates and a decrease in battery life. If the diagnostic results showed about 11.6 volts, then we can conclude that the battery is completely discharged, its training will not help in this case, first of all the device must be charged (the author of the video is the Accumulator channel).

Separately, it should be said about self-discharge diagnostics. To check, you need to connect one probe, and hold the other over its surface. If, as a result of these actions, readings began to appear on the tester's display, that is, the device recorded the voltage, this indicates a self-discharge of the battery.

Battery test with load plug

In addition to the above methods, there is another diagnostic method car battery, and this method is one of the most accurate. In order to understand whether the battery is operational, it is necessary to diagnose the device's ability to perform its primary functions as a result of connecting the load. Sometimes it happens that when testing certain parameters of the battery performance, diagnostic devices show that the battery is normally charged and working well. In this case, in fact, the starter turns very hard, sometimes it does not even work to start power unit... With such a problem, it is possible that the capacity value in the battery has dropped, which leads to an instantaneous discharge of the device.

In practice, such problems are often caused by mistakes made when using the device. Battery testing can be carried out using a special device - load fork, which, in fact, is an ordinary voltmeter. Only it can be connected in parallel with the load terminals. Ideally, the resistance value in this case should vary in the region of 1-1.4 from the capacitance parameter of the device as a whole. This value is the maximum bit (the author of the video is the Accumulator channel).

First, you should test the voltage value of the device in the absence of load, this will allow you to correctly determine the degree of discharging of the device. This value is determined in accordance with the data indicated in the table, with the engine running, running on idle... When this stage is completed, the voltage parameter on the battery is tested, only now it should be loaded. Thus, you can correctly determine the value of the device's charge, and it should also be checked against the tabular data. This value must be removed at the fifth second after you turn on additional energy consumers - a stove, car radio, headlights, etc.

If the battery itself is fully charged, then the voltage value under load on the device should be about 10.2 volts or higher, but not less. In the event that the diagnostics showed less results, this indicates the need for training, as well. In some cases, without load, the battery produces a voltage of 100%, however, when the energy consumers are turned on, this indicator drops sharply, and very much, and the results are fundamentally different from the tabulated ones. In this case, we can conclude that the battery is out of order, and there can be a huge variety of reasons in this case, ranging from a short circuit to the destruction of the internal plates.

Photogallery "Correspondence tables"

1. Correspondence of parameters at load at idle speed 2. Correspondence of parameters at load for 5 seconds after switching on consumers

Conclusion

In conclusion, I would like to note that every motorist should check the battery performance from time to time and, if possible, troubleshoot. Otherwise, the battery may simply be discharged, as a result of which the normal start of the motor will be impossible. Also, the motorist should periodically perform a control-training cycle, since this procedure allows the battery to recover after prolonged use. Even if the battery is completely discharged, its charging and CTC will allow to restore its operability for a while.

How the workout is done:

The battery must be fully charged first.
Then the device is discharged to a minimum.
The next step is to charge the battery again.

Generally maintenance car battery should be dispensed at least twice a year. It is best to do this before the onset of cold weather, as well as after winter.

It's no secret that the operation of modern cars directly depends on the state of the battery. After all, the time of engines that can start from turning the lever has long passed, not to mention the fact that for the functioning of modern electronic systems responsible for driving, navigation, etc. power supply required. Accordingly, keeping the battery in good condition is important. Unfortunately, the methods of its diagnosis are unknown to many car owners. Therefore, in this article we will tell you how to check the battery with a multimeter.

The multimeter is a versatile electrical device that any driver should have with him. It can be used to measure many important parameters that indicate battery performance.

How to check the battery charge with a multimeter?

Most modern batteries have a special sensor that changes color depending on the battery charge. However, it will not be possible to obtain accurate data with its help.

How to check battery voltage with a multimeter?

In order to check the charge of the lithium-ion battery, follow these steps:

Switch the multimeter to voltmeter mode (voltage measurement) and set the range from 0 to 20V;
Disconnect the battery from the vehicle wiring;
Connect the red test lead to the positive socket;
Connect the black test lead to the negative socket;
Record your readings.

If the multimeter shows that the voltage is 12.6 volts, then this indicates that the battery does not need to be charged and is fully functional. If the reading is below 12.6, this indicates the need to recharge the battery.

In the event that the multimeter shows less than twelve volts, then the battery is completely discharged, and it is urgent to charge it. If the reading is less than eleven volts - using such a battery can burn the generator or charger, which means that it is better to get rid of it and buy a new one.

It is important to remember that to get the latest data, you need to check the charge, you need to wait 5-6 hours after the battery is disconnected from the car.

How to check the charging of the battery from the alternator with a multimeter? In exactly the same way, but now to measure the indicators, it will be necessary to disconnect the generator from the battery, obtain the necessary data, and, if necessary, put it back on additional charge.

How to check the battery capacity with a multimeter?

Another important indicator is the battery capacity. This characteristic shows how much charge it will give during a specific period of time, at a specific voltage, and it is measured in ampere-hours.

The capacity of a car's battery can be checked with a multimeter in several ways.

Checking the capacity of the car battery under load

One way to check the battery capacity with a multimeter is to apply a load, which can be a regular light bulb. It is worth remembering that if it begins to fade gradually, then the check can be completed at this, since the battery is inoperative.

The load for testing the battery must be selected in such a way that it can take half the battery current, that is, if the capacity is 7 Amperes per hour, then the load must be 3.5 Volts. An excellent option could be a car headlight with a power of 35-40 watts.

Step by step, this procedure looks like this:

The battery is disconnected from the generator;
The battery should work under load for about two minutes;
A multimeter is connected to the battery in voltage measurement mode;
Indicators are taken.

If the battery is good, then its voltage should be above 12.4 Volts. Accordingly, any problems during startup are most likely caused by a malfunction of the electrical wiring or other systems of the car. In the event that the multimeter readings are in the range from 12 to 12.4 Volts, then this means that it will not work for a long time and will soon need to purchase a new battery.

In order to check the battery in this way, it is necessary to fully charge it and load it so that the discharge current strength corresponds to the calculated value, which is indicated in the battery passport. In this case, an ammeter or multimeter is included in the circuit, which is included in the mode of displaying the current in the circuit.

After that, it is necessary to register after what time the current will decrease by more than 50%. The resulting value is compared with the passport data of the battery and if the difference is not great, then it is quite usable. If the difference is large, then this is a clear indication that the battery needs to be replaced.

How to check battery amperage with a multimeter?

Despite the fact that voltage (charge) and capacity are the main characteristics for the successful operation of batteries, a considerable number of drivers are interested in how to check the battery current with a multimeter or ammeter.

First of all, you must remember that it is useless to measure the current strength directly on the battery. Moreover, it can lead to a short circuit.

In order to check the amperes of the battery with a multimeter, it is necessary to take readings directly from the electrical circuit. However, it is worth remembering that given characteristic will largely depend on the number and type of connected devices.

Video - Battery Test

Main fuel modern car it is not gasoline or diesel, but electricity. Without it, not a single main or auxiliary system will turn on, and even the engine will not work. The source of energy is the battery, the state of which many drivers do not even think about until it fails. This article discusses how to check the battery with a multimeter, so as not to find yourself in a difficult situation where you cannot do without outside help.

A multimeter is a device that any car owner should have. It allows you to quickly and in "field conditions" determine the mass of indicators:

voltage;
battery capacity;
resistance;
temperature.

Some modern batteries are equipped with a charge indicator, which greatly simplifies the life of the driver, but such batteries are 20-30% more expensive than conventional equipment. Having a multimeter, you can easily, quickly and with a sufficient level of accuracy determine a lot of important parameters related to the battery.

How to check battery charging with a multimeter?

Determining the state of a lithium-ion battery (the most common type of modern battery) is quite simple if you follow these guidelines:

Disconnect the energy storage device from the car and wait 5–6 hours.
The multimeter should be in voltage mode (voltage test).
A standard lithium battery can supply current in the 12.7-13.2 volt range. The switch is set to 20 or closest to it. So the voltage is measured from this value and below.
The wires from the device are connected to the battery: red to the positive terminal, black to the negative. If the wires are of the same color, then you should be guided by their markings and connect to opposite charges, minus to plus and vice versa.

Depending on the performance of the device, a decision should be made about the replacement or further use of the battery.

12.7-13.2 volts - the battery is charged and ready for use;
12.1–12.4 V indicates that the battery has been charged by about half and it is desirable to increase the energy level;
11.6-12 volts - severe depletion and the battery is not suitable as a source of electricity;
Below 11 and V - the equipment is completely out of order and attempts to use it can lead to breakdown.

To understand how to test a car battery for performance with a multimeter, you do not need special knowledge or special equipment, enough time and adherence to the listed tips.

How to check the battery capacity with a multimeter?

The capacity of the battery is the amount of stored energy that the battery can deliver over a specific period of time. The value is measured in ampere-hours. There are two ways to determine its value: test under load and the test discharge method.

How to check the battery capacity with a multimeter under load?

Each factory battery has a marking on the case, where the capacity value is indicated. Over time, it begins to decrease and the real numbers become lower than the declared indicators. To determine the feasibility of further use of the equipment, a load is required. The headlights of a car or even an ordinary 35–40 W bulb can act as a load.

Let's take a step-by-step look at how to check the battery charge with a multimeter:

The battery is disconnected from the generator;
Connect a light bulb to it and observe the operation of the electrical circuit for two or three minutes;
Disconnect the elements and take readings from the battery with a multimeter, after turning on the voltage measurement mode.

If the readings on the screen of the device exceed 12.4 units, then the battery is operational. A value of 12-12.3 indicates the need to replace equipment soon.

How to check the battery capacity with a multimeter using a test discharge?

For this type of capacity determination, you will need to fully charge the battery and connect it to an electrical circuit that has a load equal to or close to the values \u200b\u200bstated in the technical passport. Additionally, a multimeter is connected, operating in the ammeter mode.

You will need to wait a little for the current to drop by half, note how much time has passed, and compare with the values \u200b\u200bindicated in the passport. If the indicator differs by an insignificant amount, then the capacity of the equipment has not decreased much and it can be used further. Big difference in numbers means it's time to look for a new battery.

How to check for battery leakage with a multimeter?

Leakage current is an indicator that indicates the energy consumption to maintain the functioning of third-party devices connected to an intact electrical circuit. For each battery, there is a minimum leakage current value, which averages 55–80 mA relative to a car battery.

To know how to check for battery leakage with a multimeter, do the following:

Prepare vehicle to measure. Disconnect everything that consumes the electrical charge of the system and wait a couple of minutes.
Remove the positive terminal from the vehicle battery.
Connect the multimeter probe with a negative value to the terminal of the machine.
A wire with a plus - to the power battery.

After that, you need to take readings from the device screen. If they exceed the norm, then you need to turn off and put back the relays and fuses one by one, measuring the changes in the leakage current. After disconnecting one of the relays, the numbers will return to normal, hence it is the weak link in the chain.

How to check the "amperage" of the battery with a multimeter?

To determine the amperage that your battery produces, you need to create a circuit with a load. Its role is played by any device or equipment that consumes electricity. To measure, you need to take the following steps:

The device is installed in the ampere measurement mode, and the switch on it is set to alternating current, which is designated by the English letters AC.
Disconnect the terminal from the positive battery and put the negative wire of the measuring device in its place.
To the equipment that acts as a load, connect the negative terminal of the battery and the meter probe with a positive charge.
Depending on the design, look at the displayed number or read it off on the scale of the device.

A serviceable and fully charged battery demonstrates indicators in the range of 12.6-13 V.

How to check battery voltage with a multimeter?

The voltage can be measured with the engine running. A satisfactory indicator is considered a value of 13.5-14 V. It indicates that the battery can safely continue to be used.

If the number on the gauge exceeds 14.2 V, the battery is not fully charged and the generator is boosted to power all dependent vehicle systems. But you should take into account the surrounding situation when measuring, on a cold winter night, the battery could be discharged and the generator generates increased voltage to fill it. Wait 10-15 minutes and repeat the procedure. If the values \u200b\u200bhave decreased, everything is in order.

If, when checking the battery voltage with a multimeter, with the engine running and disconnecting power-consuming systems, the device shows below 13 V, then this indicates an interruption in the operation of the generator, which is not able to fill the battery to the required level.

How to check the battery with a multimeter with the engine off?

The average indicator, when checking the battery with a multimeter, on an idle motor should be in the range of 12.5-13 V, while the upper value indicates 100% charge, and the lower value indicates 50%. The numbers are approximate, but the big picture is easy to understand. Also, do not forget that you should take readings immediately before the trip, and not after it, as soon as you turn off the engine. It is especially good to carry it out when the car has not been used for some time, for example, in the morning, after a night in the garage. This shows how well the battery can hold a charge.

Now you understand how to check the battery charge of a car with a multimeter. This device is worth buying for every motorist. Some rely on the readings of the on-board computer, but it does not provide sufficient accuracy. The built-in voltmeter is connected to a chain of devices that consume energy, and not directly to the battery, therefore, part of the electricity is consumed "on the road".

What are the ways to test a car battery for performance?

When operating a car, you periodically need to pay attention to the maintenance of some of its components, including the battery. Many car owners are aware of this, but often simply do not understand how to check a car battery. There are a number of techniques for this, which we will talk about below. To correctly test the battery for performance, devices such as a multimeter and a load plug are required. If you are constantly going to independently service the battery, then it is better to purchase them. In stores, these devices can be found at an affordable price.

When checking a car battery, it is worth starting with its external inspection. This is a simple but important step. It shows surface contamination battery, oxidation of leads, damage to the integrity of the case. External inspection of the battery should be carried out regularly, since its cleanliness also affects its performance. You can do this every time you look under the hood. Taking a quick look at the battery doesn't take long.

Pay attention to the connections of the terminals to the current leads. With a poor connection, active oxidation takes place there. The battery case is visually inspected for cracks.

The battery surface must be clean. Dirt, dust, electrolyte, oil must be removed with a cloth. Otherwise, the battery will constantly lose charge through this conductive coating and performance will deteriorate.

Of course, it is worth checking the reliability of the battery fastening in the seat. Now let's talk about how to check the car battery using various devices.

Checking the battery with a multimeter

The multimeter can measure the voltage on the battery. To assess the battery charge, the voltage is measured at the battery terminals without load. For this, the multimeter is set to voltage measurement mode. Then touch the positive terminal with the red probe, and the negative terminal with the black one. If the battery is fully charged, the voltage will be 12.6-12.9 volts. It's okay if the probes are connected the other way around. In this case, the multimeter will simply show the voltage with a minus sign.

Some readers ask how to check a car battery with the engine running. The fact is that on a running engine, it is not the battery that is checked, but the presence of charging on it from the generator and the serviceability of the voltage regulator.

The voltage at the battery terminals when the motor is running should be in the range of 12.9-13.4 volts. If it is less, then the battery will be poorly charged, and if it is more, the process of water electrolysis is activated.

It should be noted that with the help of a multimeter, you can only assess the state of charge of the battery. To assess its performance, you need to know how to test a car battery with a load plug.

Battery test with load plug

The load plug is a device that creates a load on the battery similar to that experienced by the battery when starting the engine in a car. Such a check of a car battery allows you to objectively assess its condition and performance. This device includes a voltmeter, load resistor and terminals.

To check, connect the terminals of the load plug to the battery terminals. The voltmeter should show a voltage between 12.6 and 12.9 volts. If it is less than this value, then the battery must be fully charged. Then the load is applied for 5 seconds. After this time, the voltage at the terminals should not fall below 10.2 volts. If the voltage has dropped below 9 volts, then the battery is already badly worn out. If the value is less than 9 volts, then such a battery is definitely time to change.

Now you know how to test a car battery for performance using a load plug. There is another interesting point here. We considered the case when a charged battery has a nominal voltage of 12.6-12.9 volts. What if the battery voltage is less? In most cases, this indicates that one or more cans are out of order. Most often this is caused by a short circuit of opposite plates, which leads to a loss of performance.

How to test a car battery for a short? This can be done using the same multimeter. We connect the probes of the device to the terminals of the charged battery and look at the readings. If the voltage is 10.4-10.7 volts, then one of the cans is out of order.

A cell (or bank) of a battery in a charged state has a voltage of 2.1 volts. So, according to the readings of the multimeter, you can immediately determine how many elements are out of order. To determine a faulty jar, you need to measure the density of electrolytes in all. In a closed jar, the density will differ sharply from the rest, and when charging, there will be no gas release in it (as boiling is also called).
Additionally, you can read the material on the specified link.

Checking the real battery capacity

As you know, the nominal capacity of the battery in the general case is determined by its design features and production technology. The manufacturer always puts the value of the nominal capacity on the battery label. But the real value of the capacity during operation is constantly changing downward. Naturally, this decreases the power and performance of the battery. How to check the car battery by the real value of its capacity?

For this, a diagram of the following type is assembled.

The resistance in this circuit is calculated by the formula:

I is the discharge current.

The discharge current is selected depending on the duration of the discharge cycle. This is usually 10 or 20 hours.

If you are lucky enough to become a car owner, then sooner or later you will be faced with a situation where you need to know the battery charge level. It doesn't matter if you bought new car or has already been in operation. In our article, we have prepared instructions on how to properly check the battery and not be left without an "iron horse" at the most inopportune moment.

Features of a dead battery

Even novice car enthusiasts, with constant car operation, notice when the car starts to malfunction. And at one point the car just stops starting. A dead battery can do this. Typical features of battery problems are:

Sluggish scrolling of the engine crankshaft by the starter. Or the starter does not turn at all.
Rapid loss of charge. This is especially noticeable during cold weather.

If you find any of these signs, don't ignore it. To get started, you can check the battery at home before going to a car repair shop or buying a new battery.

External inspection of the battery

Check regularly appearance battery is desirable every time you decide to look under the hood of a car. After all, even simple dirt on the case can lead to premature discharge.

If the case is cracked, check if it is securely fastened. Poor retention will shake the battery and deform the plastic.

Electrolyte leaks, dust and dirt near the battery terminals form contaminants leading to self-discharge. It is necessary to clean the joints with a soda solution and wipe dry.

If there are sour terminals, make sure the terminals are tightly fastened. Sand the terminals with an emery cloth or metal brush, and treat with acid-resistant grease.

Battery tester

An external inspection of the battery will indicate visible shortcomings in operation, but "by eye" the charge level cannot be found out.

To help motorists, we present a couple of testing devices for testing batteries:

Multimeter
Load fork

Tester check

To obtain accurate battery charging results, measurements are best taken a couple of hours after charging. The battery passport indicates the charge range and in most cases it does not exceed 12.9 volts.

Step-by-step instruction:

Set the handle to the state direct current (DCA).
Insert the positive (red) lead wire into the connector with a range of 10 to 20A.
Insert the negative (black) test lead into the common connector (COM)
With the red probe, touch the positive battery terminal, with the black one touch the negative terminal.
Read the data from the device display and compare with the technical documentation for the battery.

Remember that the duration of the battery test with the tester should not exceed 2 seconds, so as not to damage the battery.

The voltage of a fully charged battery must not be less than 12.6 W. A 12W charge indicates that the battery is 50% low and needs recharging. At 11.5 W we get a completely discharged battery.

Load fork diagnostics

Testing with a multimeter alone is not enough to comprehensively check the battery condition. The next step is to test the battery with a load plug.

In practice, it sometimes happens that when checking the voltage, the data shows a full charge, but in fact the starter either turns badly or does not turn at all. This can be caused by improper use of the battery for a long time. Therefore, it is necessary to check the battery operation under load.

The load plug is a voltmeter with a clamp and a load lead. We connect the terminals to the battery terminals (+ / +, - / -). Measurement duration no more than 5 sec.

We fix the indicators. If the voltage is 10 W or less, the battery needs recharging. When getting a 9W figure, consider changing the battery.

Electrolyte level check

After eliminating external deficiencies and measuring the voltage, we proceed to the next step. Before checking the electrolyte level in the battery, open the can caps and look inside.

The electrolyte level is considered normal when it covers the plates by 1.5 cm or more. For an accurate reading, take a glass tube (approx. 3 mm diameter) and dip into the hole, plugging one end with your finger.

If there is little electrolyte, then the plates will rise above the liquid. In this case it is necessary to add distilled water.

Electrolyte density check

For adequate battery operation, it is necessary not only to regularly measure the electrolyte level, but also its density. This can be done using special device - hydrometer.

It is a glass flask with a pear and a pipette at the end. Inside the flask there is a measuring scale and a weighting agent. How to check the battery with a hydrometer is shown in the photo.

It is necessary to open the plugs on all battery banks. Then, one by one, electrolyte is collected from each jar with a pear. The float should float freely. The density is measured in each jar.

When receiving data within the average value (1.27-1.29 g / cm3), then nothing needs to be done with the electrolyte. If the numbers are lower, then add distilled water. If more, then take from a jar with a higher density of electrolyte and pour into it.

A few words in the end

Externally inspect the battery regularly
Measure the electrolyte level at least once a quarter.
Do not let the battery drain completely
Bring the battery indoors during the stroke

In our article, you learned how to perform a complete battery diagnosis. Each has pros and cons. Which one to use is up to you. But do not forget that a battery can last for a good owner for many years.