How to charge a cordless screwdriver. battery charging time

How to charge and store an electric screwdriver battery

The electric screwdriver is one of the most popular power tools for home and professional use. It allows not only screwing and unscrewing different types of fasteners, but also drilling holes. The devices are divided into mains-powered and battery-powered. Battery models are almost as good as 220 V tools in terms of performance. They can also be used for carrying out work in stand-alone mode. It is also convenient that the supply cord does not restrict movement. But the battery of an electric screwdriver should be properly charged and stored so that it will last a long time. Many problems with the battery pack can be fixed yourself, using a multimeter to identify the cause of the malfunction.

The battery is the energy source for the cordless screwdriver models. Through the course of physical and chemical processes (electrolysis), this element stores electricity and then outputs a constant voltage of the desired value at its corresponding outputs. Voltage and capacity are the main parameters of any storage device. The first indicates the potential difference between the cathode and anode of the battery. The voltage is measured in volts. Capacity describes the amount of current produced per hour by the battery, so this parameter is measured in ampere hours.

In different models, the battery pack (battery) looks and is designed similarly. It consists of the following structural elements:

• the housing with the contacts on it;
• the supplying elements (batteries);
• Temperature sensor circuit (thermistor), which acts as a protection unit against overheating (the range is from 50 to 600 degrees).

Not all models are equipped with thermistors. The housing is usually a plastic box consisting of two parts. It has, generally, about 10 batteries inside, but sometimes there are more. The batteries are connected to each other in a chain. The free terminals of the outer banks are connected to the contacts located on the housing, designed to power the electric motor of the tool and to connect it to the charging equipment. Battery output voltage is determined by adding the given parameters of all the batteries connected in a single chain.

• 2 power (“, “-“), intended for charging and discharging;
• One control top connected to a thermistor;
• one contact used for charging from special stations that are capable of equalizing the charge of all the batteries present in the unit.

According to the type of battery cells, battery storage units are divided into the following types:

• Nickel-metal hydride batteries (labeled NiMh) with an output voltage of 1.2 V;
• Nickel-cadmium batteries (labeled NiCd) also output 1.2 V;
• Lithium-ion batteries (designated by the Li-Ion symbol) which have a voltage dependent on the number of cells in the battery which can be between 1.2 and 3.6 V.

Li-ion batteries have a control board. At the same time, a special controller monitors the operation of the batteries.

A separate battery consists of the following structural elements:

• positive and negative contacts;
• electrode with a positive charge;
• the external coating of the case;
• electrolyte;
• negative electrode.

Nickel-cadmium energy storage batteries are the most popular because of their affordable price, compact size and high capacity. They can be recharged more than 1,000 times.

Charging features of different types of accumulators

See below for charging options for different types of rechargeable batteries.

nickel cadmium cells

Ni-Cd batteries have a very fast “memory effect. This is worth considering for owners of Bosch PSR screwdrivers. Therefore, it is necessary to discharge them to zero. Otherwise the batteries will quickly become unusable.

• Before charging, the nickel cadmium cells must be discharged.
• Connect the charger and wait for it to disconnect when the battery is fully charged. The indicator on the charger will let you know.
• In some cases the charger is not designed for auto shut-off. Then you have to wait for the end of charging and manually disconnect the charger.

Producers sometimes allow themselves to be deceived. On average, a NiCad battery lasts 500 hours. But it’s not uncommon to see the number “1000” in a screwdriver manual. You should be aware that this amount of time is only required for the tool to work under near-ideal conditions. For example, a Vinzor electric screwdriver will run for less than 500 hours.

Nickel-metal hydride

These batteries also have a “memory effect”, although not as strong as cadmium batteries. Nickel-metal hydride (Ni Mh) batteries are fully discharged before recharging. Charge and discharge five times before use.

Lithium-ion batteries

The very first undemanding and popular battery for an electric screwdriver. No “memory effect”. Lithium-ion (Li-ion) cells, new or used, can be charged at any time.

• It is better not to charge fully discharged Li-ion batteries. It is desirable that the remainder of the charge is 20-40%.
• The suitable temperature for charging should be between 10° and 15° C. Since lithium-ion batteries are not afraid of cold, you can work with an electric screwdriver at temperatures down to.10 ° C.

How to charge an electric screwdriver with a car charger and is it possible?

An electric screwdriver with an autonomous power source is definitely one of the best inventions of mankind, and it greatly facilitates the life of almost the entire male population of the earth. Assemble furniture from IKEA, install a shelf in the bathroom for toiletries or tighten the screws in the car, it can all be done with this power tool. And the greatest beauty of a cordless electric screwdriver is that it does not require the presence of somewhere near the electrical outlet, as it is equipped with a portable battery. But the battery with which this device is equipped needs to be recharged from time to time after intensive use of the device. Just for this purpose in the set with this hand-held power tool is a special charger, which can sometimes break at the most inopportune moment. And when such an unfortunate misunderstanding happens, the unfortunate owner of a discharged tool has a relevant question in such a case: can an electric screwdriver be charged with a car charger and how in principle to do it so as not to damage its battery definitely and irrevocably?

If it so happened that you urgently needed an electric screwdriver, and his battery is discharged and there is no suitable charger nearby, you can charge the battery screwdriveravtomobilnoy charger to do this should do the following manipulations:

• disconnect the discharged battery from the handle of the electric screwdriver;
• Determine the capacity and operating voltage of the battery, these data are usually written on the body of the power source;
• adjust the current input to the car charger according to the electrical characteristics of the electric screwdriver battery;
• Connect the car charger without reversing the polarity to the battery terminals of the electric screwdriver and charge it for about 30 minutes under your own constant supervision.

It should be noted that such a procedure can be performed 1, maximum 2 times. If you do so more often, then the question whether you can charge the battery of an electric screwdriver car charger will disappear by itself, because there will be nothing to recharge because its battery will simply fail due to incorrect operation. But the best option, if the original charger is lost or broken, is to buy a new compatible battery charger for an electric screwdriver on MegaBattery.The screwdriver will be charged at a reasonable price and with a 1 year warranty. Then the question whether you can charge the battery of an electric screwdriver with a car charger will no longer be relevant, and its battery will avoid extreme loads and serve well for a long time without unexpected failures and breakdowns.

How much to charge the battery of a Bosch electric screwdriver

Modern devices for recharging equipment with electricity are equipped with an energy indicator. Unplug the power supply immediately after the green light turns on, indicating the end of charging. The minimum time required for this process is half an hour. It may be increased depending on the type of battery. The longest recharge time is with the nickel-cadmium type battery. It takes about 7 hours to fully recharge such a unit.

The manual for the Bosch electric screwdriver specifies the battery charging time more precisely. There you will also find a detailed description of the charging process for your battery model. It is a good idea to follow the manual completely when using the equipment. This will extend the life of both the device and the power supply. Therefore, before you charge a Bosch electric screwdriver battery for the first time, it is advisable to carefully read the instruction manual provided.

Peculiarities of recharging lithium-ion batteries

About how to properly charge the battery of an electric screwdriver with a lithium-ion battery, you may not think at all. Devices have only a nominal “memory effect”. It does not affect the general functionality. It is appropriate to recharge such a module when it is convenient, not paying attention to the current level of battery capacity.

How much time is required for recharging

Just before you charge the battery on an electric screwdriver, you must carefully study the instructions for the tool. This will certainly indicate the time required to charge the unit “to full”. These terms should be adhered to. Usually lasts from half an hour to 7 hours.

Separate screwdriver chargers have an indication system. It allows you to control the process and stop it in time when the battery has reached full power.

Lithium-ion modules need to be watched more closely. They are sensitive to full discharge and overcharging. Both of these parameters dramatically reduce the service life of the units.

temperature control nuances

Check the ambient temperature before activating recharging. Preferably not lower than 10°C and not higher than 40°C. Gaining working capacity, the battery sometimes gets warm, and overheating is categorically inadmissible. In the future this will have a bad effect on the device and reduce its performance.

Technical aspects of the process

Just knowing how to properly charge the battery of an electric screwdriver is not enough. It is very important to observe the following rules:

• Do not leave the battery in the charging module;
• Store the supply unit separately from the tool in a dry place without temperature fluctuations;
• if used seldom, to charge the modules once a month or according to the enclosed manufacturer’s instructions.

This will prolong the battery’s life and ensures that the electric screwdriver is always in perfect working order.

The influence of external factors on the battery

Each power tool comes with instructions on how to charge it. This is especially true for expensive models. The process can be performed both indoors and outdoors.

info. A 1.2 Ah NiCad battery will take approximately 7 hours to charge.

Before you put the electric screwdriver on charge, there are a number of important points to keep in mind. It is necessary to avoid direct contact of the power tool or its battery with moisture in any form. rain, snow, high humidity. It inevitably leads to a disturbance of the electrical conductivity, including the development of rust.

Exposure to direct sunlight is also detrimental to the condition of the battery and the tool as a whole. This is especially true during the summer, when the temperature rises to 40 degrees, or even more. The result. overheating of the device, breaking the electrical contact. This process is not immediately notice and symptoms will become apparent over time.

Switching a cordless screwdriver from Ni-Mh to Li-Ion

We will talk about cordless screwdriver Werk SD-362 is widely known in small circles, but in fact produced by order of the Stroydepo chain stores.I bought it in 2013 on the principle that I liked the look and feel, and if it also works. then even miracle. Cost a modest 350. Well, it’s not a sin to take. Often I have to unwind welding inverters, uninterruptible power supplies, microwave ovens and other junk. An electric screwdriver is too big, but a cordless screwdriver is fine.I used it in a total of about 1.5 years. Then I catastrophically ran out of power. (I always carry with me a case of the essentials of electronics, sometimes the tools are not used for a couple of weeks, sometimes a whole month in the work) As a result, the screwdriver held about a week, then you need to charge it. and if the work is urgent, this is out of the question. There is a problem. how to convert the screwdriver to Li-Ion as cheaply as possible.The internal arrangement is typical of such screwdrivers:

1) housing2) RS380S motor 3.6V3) A pack of 3 NI Mh batteries 1.2V4) A button that switches the direction of rotation

It was decided to change it to Li-Ion battery.Advantages of this solution:1) low self-discharge2) weight3) no memory effect (no need to discharge the battery to zero to put it on charge)4) indication of charge5) indication of the end of charge

Disadvantages of this solution:1) the battery charging circuit is a bit more complicated

As a result, after careful consideration and looking through solutions for charging Li-Ion batteries, I chose a solution based on the TP4056 chip from Ali-Express:

Next comes to the most remake: Battery I used form factor 18650 capacity of 2200 mA / h LGDAS31865

We remove the block indicating the remaining charge

Remove the USB connector from the TP4056 charger board

We install the board with TP4056 and wiring in place of the charging indicator block.To charge it will be through a regular screwdriver charging jack. But for normal TP4056 functioning it needs 5 V. And regular power supply unit gives 6 V (and more at idle).To correct this defect, L7805 was unsoldered from the burnt UPS (stabilizer with a range from 7 to 25 volt). The circuit diagram from the description of the chip:

Capacitors were mounted by hinged mounting

Testing the location of the regulator with the elements in the case

Assembled (the charging connector is not yet installed)

In the empty holes I will insert the light guide for better display of the beginning and end of charging.

(The cost of the TP4056 board) and the rest was assembled from the materials at hand.) A nice bonus was the ability to use any unit with voltages from 7 to 25 volts for recharging

Skil Electric Screwdriver/Minishurik reconfiguration for Li-Ion battery power

Greetings, everyone who dropped by. In this review we are going to talk about, as you probably already guessed, a simple re-design of Skil Mini Screwdriver / Mini Scratchpad powered by a Li-Ion battery using affordable components. The result is a minishurik with a high-capacity lithium battery, built-in battery charging and protection against overcharging/overdischarging and short circuits. If you are interested, please follow this article. The Skil Electric Screwdriver / Mini Screwdriver itself: What can I say about it. it is an old model, powered by NiCd AA batteries. The handle is not very comfortable. in the form of a skirt. The electric screwdriver itself is very compact, so I decided to re-do it, not to carry a full-sized Makita Ni-Cd electric screwdriver. With this easier. put in a / duffel bag, not a lot of space, and the average length of screws (30-40mm) twists like hell. The main advantage of the conversion. there will be no wild self-discharge and memory effect in batteries, so it will always be ready to use. At the worst, you can connect the charger half an hour before the upcoming work and do not worry about reducing the capacity of batteries. At work I have a Makita screwdriver with NiCd batteries, so often you take it out of the case and you don’t know if it will be enough to tighten a dozen screws. After all, it is not recommended to charge nickel batteries without fully discharging them, because they have a memory effect. Therefore, after spinning a little, and throwing for a month in the closet, at the next need of an electric screwdriver do not know how much charge is left. I already mentioned before the advantages of lithium power supplies (Li-Ion/Li-Pol) over nickel power supplies (NiCd). In our case the comparison is only with NiCd batteries, because only they can supply a high current:. high energy density. In the minidriver is a cadmium battery 4S 4,8V 800mah stored energy 4,80,8 = 3,84Wh, and a lithium battery 18650 3,7V 3000mah. 3,73 = 11,1Wh. As we see, the energy is higher, the capacity is larger, and the size is slightly smaller. And this despite the fact that the nickel assembly was taken into account, not a single battery. no memory effect, t.е. it is possible to charge them at any moment, without waiting for complete discharge. smaller size with the same parameters with NiCd. fast charge time (do not be afraid of high charging currents) and clear indication. low self-discharge From the disadvantages of Li-Ion can be noted only:. low frost resistance batteries (afraid of negative temperatures). requires balancing of the battery during charging (in case of 2S or more) and the protection against overdischarge As we see, the advantages of lithium are obvious.

The screwdriver was charged with the following adapter designed for 7,5V/230ma: It is not difficult to guess that there was no bank control, because the charging current is small.

Brief Technical Specifications:. Manufacturer. SKIL. Model. 2148AA. Body. shockproof plastic. Rated voltage. 4.8V (4S). Battery type. 4 NiCd batteries connected in series (AA/fingers). Declared capacity. 1100mah (actually installed at 800mah). Battery level indicator. no. Chuck type. for bits, with 25mm extension. Gear. planetary, Metal. Maximum torque. 3,5Nm. Number of steps of torque (ratchet). No. Speed selector. No, one speed (180 rpm). Speed regulator. No. Reverse. Yes. Automatic spindle lock. Yes. Backlight. No. Dimensions. 190mm190mm55mm. Weight. 400g

Now let’s see, how the electric screwdriver is set up from inside. To disassemble it is necessary to unscrew the 5 screws: After that the body opens into two halves: Gearbox, most likely planetary, gears made of metal. Collector motor, designed for 4,8V supply: And here we have four NiCd batteries, connected in series (4S), capacity 800mah, although many sites says 1100mah capacity: Direct redesign of Skil electric screwdriver / minitool:

I will remake under widespread cheap lithium f/f 18650, paralleling a few cans. “Why for Li-Ion batteries f/f 18650 with a connection 1S (in parallel)?”. you ask. Yes, because the low voltage minishurik is pretty fast and will be used at work not so often, in addition, I had to attach a few dying batteries from a laptop battery. I know I could install 4 pcs of 14500 TrustFire 900mah into the coil without much trouble, but first of all, it’s not my screwdriver at work, and secondly 14500 lithium is expensive in terms of price/capacity, and capacity doesn’t shine. I didn’t want to fool with BMS boards on 2S connection, because the case of minishurik is very compact. I will use this half-dead 18650 lithium (Samsung ICR18650-22E 2200mah), once placed in a laptop battery (cans, again, not mine): As you can see, it is clearly larger than the seat: These half-dead cans were 3 pieces. Their capacity is not particularly inspiring, but the sum is not bad (4000mah): I recommend installing high-current batteries, a list of which is at the end of the review. Batteries will be placed vertically, so part of the housing “skirt” can be sawed off: The banks themselves will be placed in a plastic sewer pipe. As the saying goes, what was on hand at the moment, that’s what I used: According to the idea it should turn out like this, the bottom is made of plywood, for rigidity of the future handle: Not everything is as simple as we would like it to be. Though the banks are half-damaged, but I wanted to make everything “by the rules”. with protection against overdischarging, overcharge, and with the built-in charger module. As you probably figured out this is a “national” TP4056 Li-Ion battery charging board and a protection board for medium current 18650 Li-Ion battery. The first will charge the banks correctly, and the second will protect against overdischarge and short circuit (short-circuit). I don’t recommend to do without protection board, you can very much reduce battery life by overdischarging, although at 2V traction is quite small. Protection boards from normal protected Li-Ion batteries will not go, because the current in the minishurik even though small, but sometimes exceeds 3-4A, and it is for these currents and are designed this board. I took a protection board from medium-current battery Sanyo NCR18650GA 3500mah, about which I wrote a review earlier: Do not use ordinary boards from low-current batteries, because they have a current limit of about 5A. The connection is very simple: Roughly speaking, the “” is common, the minus from the TP4056 can be connected either to the whole minus plate (in the photo on the back side) or to the “P-” pin. The motor can be connected to the TP4056 pins, whichever is more convenient. Since the TP4056 charging board is long and I don’t need the miniUSB connector, you can safely neuter the board. I have already written about this many times in my reviews. In this case carefully go through the board with the blade and break off unnecessary part: The main thing is not to take close to the resistors. Then clean up the same blade blade pads: Then solder, plus to plus, minus to minus, you can directly or with wires, whichever is more convenient: The main thing that the module was placed and did not interfere: Then solder protection board: Then solder the batteries. How to do it, already described in detail many times. I can add that it is better to use active flux (solder acid) and a powerful soldering iron (60-80W). The acid then erase with alcohol/acetone. It goes something like this: The isolone here serves the following purposes: to protect against bumping and to prevent the resulting handle from squeezing. Then we put all these things into the case in their places. I recommend to insulate all internal parts with tape just in case: assembling, glue or epoxy on the handle. It looks a little bit homemade but it is good for work: As a result we have pretty good capacity, pretty compact size. Charging is much easier than it seems. I cut off the wire with DC plug 5mm from the existing charger and soldered the USB plug to its free end: Now you can charge the electric screwdriver from any source with USB output (power adapter/PB/PC): Maximum charging current. 1A. Since my banks are not heavily discharged and it takes quite a long time to discharge them, the charging current is a little less: Everything seems to be fine, but there is one important nuance, namely the blocking of the protection board when it triggers. Т.е. if the spindle of the minishurik is blocked, the protection board gets locked and can only be reset by turning on the power, i.e. by plugging in the charger. It is clear, that it is not kamilfo to take another charger for work, therefore we are going to improve the scheme. A typical circuit of a protection board is as follows: To release the lockout, apply voltage to the BATT and BATT pins. To do it let’s introduce miniature button which short circuits: I’ve found an old button, you can use some similar ones: We drill holes in the case and glue button on superglue: We solder two wires and as a result we get such kolhoz: When lock works, we press button once and voila, lock is off. When you screw in large screws, the button can be permanently clamped, then there will be no current limit, but the button can not withstand a large current. In general, it is better to use the spindle lock and twist with the knobs. The indication itself is charged/charged: A small note:

Is it possible to charge the lithium-ion battery without a controller

Many people wonder if it is possible to charge the lithium-ion battery without using the controller. This is actually possible. However, you will have to keep a close eye on the voltage and charging current. It cannot be allowed to be too high. The fact is that higher values can lead to the fact that the battery will fail and then it can not be used.

To safeguard your electric screwdriver with a lithium ion battery, you have to limit the maximum charging current yourself. Only then can you recharge without using a controller.

Additional information! This method of recharging is rarely used, because many people do not want to monitor the voltage all the time. It is better to use universal chargers. With their help, charging a dead electric screwdriver is many times easier.

Some people don’t know how to charge an electric screwdriver without a charger and immediately buy a new charger. However, you don’t actually have to do this. There are several effective ways to recharge the tool at home, even without the use of a brand-name charger.