Reasons not to upgrade
If a part is found to be defective, the owner involuntarily has doubts about the need and expediency of repair. For this reason, it is fair to warn about those moments that can become an insurmountable difficulty for the user:
- As mentioned above, due to the inability to increase or decrease the charge of lithium cells beyond the allocated limits (4.2V above and 2.7V below), a charge-discharge controller will need to be connected.
- The cadmium analog is in the lower price segment.
- Low temperatures can render lithium batteries unable to function properly. This makes it impossible to use the tool outdoors in winter.
- In some cases, it is not possible to transfer the charger for cadmium variants in a new way. This will require the purchase of a universal or dedicated charger.
- The modernization carried out, especially after the introduction of the charge-discharge controller into the case, will make the tool inconvenient to use.
It is possible that the presented arguments can convince the user to convert to lithium counterparts.
Assembling the battery
After checking the internal resistance of each cell, it is allowed to proceed with the assembly of the battery. The collected cells are placed in the bag, taking into account the polarity. Then the balancers and power wires are connected, the packages are connected to each other.
There are 2 techniques for connecting the battery. soldering and bolting. Soldering the part means ensuring the reliability of the connection, but if you are not confident in your own skills, it is better to choose an alternative option and select the elements intended for bolting.
After the tie, all the elements are placed in a pre-prepared box with a hole for cables. BMS board and balancers are mounted. After the output of the power wires, the holes are sealed.
Removing the battery case
Each user is able to independently disassemble the case, which consists of two parts connected with screws and glue. The screws are unscrewed, the glue layer is broken with a thin object, which is pushed along the entire perimeter.
After the repair, the screws are installed in their original place, and the adhesive layer is renewed.
Features of the choice of lithium batteries
The lithium-ion generation is the most modern. When choosing a battery, you need to pay attention to the following indicators:
- Number of discharging and charging cycles available (latest models are capable of discharging up to 600 times).
- Charging speed (maximum 2 hours).
- Price (no more than 50% of the cost of an electric screwdriver).
- Full Power Feature.
- Battery level memory.
- Self-loading.
- Dimensions (edit).
- Resistance to temperature extremes.
Soldering power supplies
There are several methods of soldering, the most common is soldering with a metal strip that can be removed from the can. Places of future contacts on both sides are tinned with a heated soldering iron with a drop of solder. Without bringing to strong overheating, a tape is applied.
Conversion of an electric screwdriver 12/14 volts to lithium batteries
After a while, the battery of the electric screwdriver will get tired and need to be replaced. At this point, instructions on how to convert an electric screwdriver to lithium-ion batteries come in handy.
Replacing batteries in an electric screwdriver with lithium 18650 does not require specific knowledge from the user, you just need to understand the basics of repair, as well as purchase the necessary components.
Important! The lithium-ion unit has a low self-discharge level, has a high energy density per mass, and at the same time pleases with its price tag.
When connecting batteries to the board, you must follow a clear sequence: 0 V then 4.2 V, 8.4 V, 12.6 V, 16.8 V, otherwise the gadget will not work. In this case, it is important to ensure the same level of charge.
To understand how to convert a 12 volt electric screwdriver to lithium-ion batteries, you need to decide on the type of soldering. The most optimal option is spot welding, since overheating is undesirable. However, soldering is also appropriate. In order to avoid unnecessary costs that will arise from careless work, it is recommended to practice on unnecessary batteries.
In order to calculate how many 18650 batteries are needed for a 12V electric screwdriver, it is worth resorting to the following calculation scheme: 2-3 nickel. 1 lithium; 5-7 = 2; 8-10 = 3; 11-13 = 4.
Preparatory stage
Haste will never lead to the expected result. Step-by-step instructions for changing batteries begins with the preparatory stage.
Before starting work, it is necessary to determine the number of units used in the battery, which will significantly affect the level of the final voltage. It is equally important to select the correct lithium component to be used. The indicator of discharge current and capacity deserves special attention. Don’t forget about the controller too.
The characteristics of the part are compared with the indicators of the rated voltage and discharge current. In other words, to assemble 14V power supplies, you need a controller with the same voltage level.
Restoration of cans
Do not rush to throw out batteries that have not passed the test. The main prerequisite for their failure is the evaporation of water through a sealing gum located between the body of the middle tire. When it has a complete “zero”, the battery is briefly charged by impulse supply of 12 V voltage through a resistance of 40-50 ohms. With all this, you should keep it under control so that the case does not overheat. If later, as before, he does not have tension, it is natural to throw out the jar.
We measure the voltage
Before measuring the voltage of the cells, prepare a simple pencil with which you will write down the value of U issued by each battery in the bundle. Since in most cases “walking” screwdrivers are equipped with nickel-cadmium batteries packed in dense cardboard layers, it is important to ensure that the batteries are accessible from both sides.
Now it remains to turn on the voltmeter (or multimeter) and start measuring. When measuring, we make each battery an exposure for five seconds and see if the voltage drops (usually it is normally about 1.2 volts for each battery separately). We fix the indicators with a pencil. It is impossible to keep the probes on batteries for a long time, because the resistance increases, and they can simply burn out.
Practice shows that one has only to fail one element from the entire bundle, this negatively affects the operation of all batteries. If the voltage indicator on any “bank” is 1 volt or less, it has already exhausted its resource. In order to finally make sure of this, you should check the self-discharge level of each battery in the bundle.
Repeated measurements are taken after 15 minutes. When measuring, be sure to check the primary U values with repeated ones. If it turns out that there are batteries, the voltage of which after the initial measurements dropped sharply during the second measurement, it means that they have a high self-discharge, and it is these elements that have already completely become unusable.
After the unusable elements are “calculated”, we disconnect them from the rest with a scalpel, and in their place we put usable batteries from a spare battery. So we redo the entire block, collecting one full-fledged from two.
How to disassemble a battery from a Makita electric screwdriver and do it yourself
Everyone knows that the battery of an electric screwdriver sooner or later begins to lose its former performance and needs to be replaced. Usually only a couple of elements in a common bundle “sit down”, but this negatively affects the entire battery. Therefore, it becomes necessary to either replace several elements with new ones, or still change the battery pack completely. Since the complete set of any electric screwdriver. “Hitachi”, “Makita” and other models. includes two batteries, if you wish, you can try to assemble a whole homemade battery from two. The owners of power tools, who use them all the time, sooner or later begin to wonder how to convert the battery of an electric screwdriver to lithium. As for the newcomers, who were puzzled by this goal for the first time, they first of all have a question about how to disassemble the battery from the Makita electric screwdriver or any other, so as not to damage the fragile plastic box.
How to convert cordless drill to corded, Black & Decker
Experienced electronics enthusiasts assemble different types of batteries, including power supplies for an uninterruptible power supply (UPS). This is much more difficult than disassembling the battery of an electric drill. Any drill is often produced with so-called “non-separable” battery packs, which are either firmly sealed with tape around the perimeter, or their two parts fit so tightly to each other that, at first glance, it is impossible to disconnect them without causing forced external damage. However, among the craftsmen you can find people who have already thoroughly “got their hands on” such batteries and can happily share their secrets with everyone.
How to disassemble a Makita electric screwdriver battery
How to disassemble a Makita electric screwdriver battery. My second
Interskol Electric Screwdriver Battery
The Interskol electric screwdriver is one of the most popular for its versatility. In addition to the main function, it can also serve as a drill. The batteries in it can be any of all common ones. Nickel-cadmium and metal-hydritic ones are used more often as they are cheaper and rather powerful. For them to work reliably, they must be fully discharged and recharged to make full use of the charge. Otherwise, the service life of the equipment is greatly reduced. Reversible loss of cell capacity during incomplete discharge and charging is called the memory effect.
Lithium-ion batteries do not have this disadvantage, but they have a much higher price. During operation, when every minute counts, a little recharging is often required to maintain the required power of the electric screwdriver. Here, such batteries are irreplaceable, since their capacity can be quickly restored.
The buyer chooses the battery of the Interskol electric screwdriver independently, depending on preferences, capabilities and the required work. Nickel-cadmium batteries are used in most cases.
How to recover the battery of an Interskol electric screwdriver if it has not been used for a long time? During operation, one must try to ensure that there is no voltage drop to zero. For a 1.2 V can, the discharge is produced up to 0.9 V. If it is completely discharged during long-term storage, then the charger may not “see” it. It is necessary to “push” the battery with another, more powerful source of current, so that a small voltage appears on it. After that, you can connect it to the standard charger.
We measure the voltage
Before measuring the voltage of the parts, prepare an ordinary pencil with which you will begin to write down the value of U issued by each battery in the bundle. Since almost always “running” screwdrivers are equipped with nickel-cadmium batteries packed in dense layers of cardboard, it is essential to ensure that the batteries are accessible from both sides.
Now it remains to turn on the voltmeter (as it is also called the multimeter) and start measuring. When measuring, we make each battery an exposure for a period of 5 seconds and see if the voltage drops (usually it is normally about 1.2 volts for each battery separately). We fix the characteristics with a pencil. It is impossible to keep the probes on batteries for a long time, since the resistance increases, and there are variations that simply burn out.
As practice shows, one has only to fail one element of the entire bundle, this has a bad effect on the workplace of all batteries. If the voltage indicator on any “bank” is 1 volt or less, it has already exhausted its own resource. To be able to completely make sure here, you should check the self-discharge level of each battery in the bundle.
Repeated measurements are taken after 15 minutes. When measuring, be sure to check the primary characteristics of U with repeated ones. If it turns out that there are batteries, the voltage of which after the initial measurements dropped sharply during the second measurement, it means that their self-discharge is the highest, just these elements have already become completely unusable.
If the unwanted elements are “calculated”, we disconnect them from others using a scalpel, and in their place we put suitable batteries from a spare battery. So we redo the whole block, collecting one real from 2.
Dismantling the battery of the Makita electric screwdriver. video
Subscribe to the updates of my blog on the link below and sell you will have the power of the Rookzhop!
Battery maintenance guidelines
- If the battery has not been used, once a month it should be discharged to the permissible load and recharged.
- It is advisable to buy an electric screwdriver with two batteries included.
- Screwdrivers must be stored and used in conditions that exclude moisture ingress.
External power supply
The idea is not as absurd as it might seem. Even a large and heavy buck rectifier can just stand near the outlet.
You are equally tied to the power supply, and to the stuck mains plug. And the low-voltage cord can be made of any length.
IMPORTANT! Ohm’s law says. with the same power, decreasing the voltage. we increase the current strength! Accordingly, the 12-19 volt power cord should have a larger cross section than 220 volts.
We build in a ready-made power supply
To do this, you need to purchase a ready-made block with suitable characteristics and dimensions. There is enough such good on the radio markets.
Take the body with you and go to the fitting. When the desired power source is purchased, carefully separate it from the case.
We place an electric screwdriver in a battery box. All components must be securely fastened.
If necessary, extend the wires connecting the control board and the transformer. If the circuit touches the metal parts of the transformer during operation, a short circuit will occur.
Since the space in the case allows. separate the board and the transformer for better cooling. Whichever quality power supply you choose, the load will be high and overheating is possible.
It will not be superfluous to fix additional radiators on the power control microcircuits. Operate the electric screwdriver for a long time, disconnect it from the mains and touch the radio parts on the control board.
You yourself will understand which elements need heat dissipation. Holes for air circulation can be made in the housing.
Do-it-yourself alteration of the power supply unit will not take much time, and the cost of the purchased module is incomparable with restoring the battery’s performance.
Making a homemade power supply
If you are familiar with the principles of building electrical circuits, you can make your own power supply. Scheme giving general concepts. in the illustration.
The transformer can be picked up from an old tube TV, or other household appliances. Power for 220 volts 250-350W. The main thing is the power supply. the donor should not be pulsed.
The voltage on the secondary winding is 24-30 volts. The secondary winding is made of a wire of the corresponding section.
Repair: 12v cordless drill battery replacement
However, if the output winding current is at least 15 amperes (see transformer specification), there is nothing to worry about.
After losses on the diode bridge (1-1.5 V on the diode), you will get the required output value.
If you have an electrical engineering education, make the calculation yourself. Or in a practical way: by connecting a 220 volt 100W incandescent lamp as a load, measure the output voltage. E
If it exceeds the needs of an electric screwdriver, reduce the number of turns of the secondary winding of the transformer.
Using a car battery charger
The principle is the same as with the use of a computer power supply. It is necessary to purchase an old charger for the starter batteries. The modern fashion for compact impulse chargers has left analog linear devices with manual control of voltage and charge current behind board. Therefore, such a device can be purchased on the automotive market for a symbolic cost.
It’s good if the voltage can be adjusted smoothly. in this case, your makeshift power supply will fit any screwdriver.
Converting it to a power tool is reduced to connecting the input of the electric motor to the power terminals of the charger.
Conversion of an electric screwdriver from a battery to a mains supply
Those who have used a cordless electric screwdriver have appreciated its convenience. At any time, without getting tangled in the wires, you can crawl into hard-to-reach niches. Until the battery runs out.
How To. Electric screwdriver repair
Using a power supply from a personal computer
On the radio market for a small cost, you can buy an old power supply from a personal computer. We need a version of the “AT” format, which had to be turned off with the key after exiting the operating system.
Experienced users remember such system blocks. The advantage of such a power supply is also that it indicates an honest power. If it says 300W, it means you can safely remove 15-16 amperes from the 12-volt output (again referring to Ohm’s law). This is enough to power the average electric screwdriver.
Such blocks have a power button in the kit. Another advantage is the presence of a cooling fan and an advanced overload protection system.
If you will hide the power supply in a beautiful case, do not forget to leave a hole for ventilation.
The connection is very simple. Black wire (-), yellow wire (12V).
Limitations. an electric screwdriver with a supply voltage higher than 14 volts will not work.
There is a way out. reworking an electric screwdriver into a network
Yes, it loses one of the benefits of a cordless tool. mobility. But for work in rooms with access to a 220 volt network, this is an excellent way out. Especially since you give new life to a broken instrument.
There are two concepts of how to make a network out of a cordless electric screwdriver: