Modern electrical equipment does not often work from the mains. To increase the comfort of use, to expand the capabilities of the tools are made more mobile, battery powered. What is the difference between such screwdrivers? Despite a little more weight, such a tool can be used under almost any conditions, there is no need to look for an electrical network, extension cords. Work becomes easy and comfortable even in the most inaccessible places, at construction sites, in summer cottages, where electricity is not yet connected.
Figure 1. Diagram of the charger for the screwdriver.
A screwdriver can have different types of batteries, they all differ in characteristics. Buying new batteries is not always justified. Using the scheme (Fig. 1), you can assemble such batteries with your own hands or repair the battery, if it is not hopelessly damaged. Before you assemble or repair the charger, it is necessary to determine its type, conditions of use. This is important because some screwdrivers cannot be used at low temperatures, others do not withstand long-term operation.
NiCd and NiMH batteries
These batteries are still quite common, although they are gradually inferior to lithium-ion as more perfect and optimal. Nickel-cadmium is used today mainly for low-cost household models, their quality is not too good.
Among the advantages can be noted:
Figure 2. Fast charging circuit.
- The service life is approximately 1000 charging cycles, which is enough for domestic use.
- These batteries charge quickly.
- It is possible to restore the current, fast charging circuit is shown in Fig.2.
- With long storage properties are not lost.
- The cost is extremely low.
But the disadvantages often outweigh the pros:
- high self-discharge;
- low capacity;
- there is a memory effect;
- the elements are toxic, i.e. their disposal must be carried out strictly according to the rules.
Nickel-metal hydride batteries are designed for professional models.
They have the following advantages:
- there is no memory effect, the battery may not be fully charged;
- capacity is high enough;
- service life is significant.
From minuses it is required to designate the following:
- The price of this type of battery is high, which adversely affects the total cost of the screwdriver.
- The discharge coefficient is large.
- The operating temperature range is small, often a loss of battery capacity occurs.
- At maximum power, working with a screwdriver for a long time is not recommended.
- It is possible to use the equipment only with constant and intensive work.
Diagram of the device lithium-ion battery for the screwdriver.
Charging batteries have the following advantages:
- The battery capacity is large, it is great for intensive and long-term work.
- There is no memory effect, i.e. if necessary, such a battery may not be fully charged, its capacity will not suffer at all.
- Self-discharge during storage of the instrument is not observed.
- Service is extremely simple, charging scheme is not difficult.
- The tool charges quickly, which is important for professional work.
But there are a number of disadvantages, among which the following should be noted:
- Long-term storage batteries do not carry so well. The screwdriver should be used often, as the battery has a certain shelf life, which you should definitely pay attention to when buying.
- You can not completely discharge the battery, as it will fail. As soon as the screwdriver began to show signs of discharge, it is necessary to replace the battery or put it on charge in order to continue working.
- In the cold, this tool is not recommended to use, as the battery will quickly fail.
Diagram of the device charger for the battery screwdriver.
The question of how to make a charger for a screwdriver with your own hands, is not so often. Today on sale you can find a variety of charging options, designed for both specific models and universal. When working in the country or a construction site, when the nearest store is far away and the tool is needed now, a charger may be required. The assembly scheme is simple, but care and caution come first. Before starting work, it is necessary to consider the conditions under which the equipment will be used. For example, at low temperatures, charging will proceed incorrectly, and the batteries themselves will discharge quickly.
If there is a screwdriver and a pair of batteries in an idle state, then they can be used as spare parts.. Careful attention should be paid to the fact that in the end charging is compatible with the battery model. Next you should take:
- battery from the battery;
- damaged battery from those that have long been unnecessary;
- wire in the amount of two pieces of approximately 15 cm;
- Phillips screwdriver;
- heat gun;
- soldering iron;
- sharp knife with replaceable blades;
If you decide to make a charger yourself, then you must follow all instructions exactly:
Table of characteristics of batteries for the screwdriver.
- First, it is required to open the prepared charging cup, after which all conductors are soldered from the terminals. The internal electronics is also removed, it is recommended to monitor the polarity of the terminals, so that during operation do not confuse anything.
- The battery case, which is the “donor”, is revealed. The wire is disconnected from the “+” terminal, after which the wire from the “-” terminal is carefully removed in the same way. To work you need to postpone the top cover and the connector. The polarity of the terminals should be noted with a marker or pencil, so as not to forget and not confuse during operation.
- Further holes are outlined, they will be located on the base of the charging glass. The holes made will be required for fastening the prepared cover and for outputting the power wires. Wires are gently passed through them, it is important to observe the polarity. After that, the power cables are soldered to the connectors and terminals.
- In order for the charger to work properly, and the connector does not fall through, you need to install a special volume simulator inside, consisting of thick paper. All covers are interconnected. If batteries are used, then such a simulator is no longer needed.
- The case is sealed with hot melt, this will give it the necessary reliability during operation.
- The bottom lid is screwed to the base of the glass.
- After that, the resulting adapter, whose circuit is simple, is inserted into the battery. Then you can start charging. If the indicator starts flashing, then everything was done correctly.
DIY battery repair
The battery circuit is not complicated, such a device can be fixed with your own hands. Repairs usually consist of replacing individual components, cleaning contacts that may become covered with dirt during operation. Experts recommend that in the absence of due experience not to recover damaged batteries with current. The problem is that an inexperienced master may overdo it during recovery, but the device circuit will not sustain it and explode. The force of the explosion is sufficient to cause significant damage, so it is better to refuse such experience using other repair methods.
There is a safer method.
Before starting work, it is necessary to measure the voltage on all elements.
In case of breakage it may be absent. In this case, the batteries are evaporated, replaced with good ones. You can buy them at any specialty store, but you need to make sure that the new elements fully match the type of battery.
When changing the screwdriver charger, it is important to pay attention to the characteristics. This includes the capacity of individual elements and their appearance. Capacity should be the same for all batteries. After replacing the mandatory charger should be recharged. In this case, it will work for a long time, there is no need to restore the charge or replace individual elements. Screwdriver will serve you more than once.