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Showing posts with the label Battery

Thermal Controlled battery charger

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One way to charge batteries rapidly without abuse is to measure cell temperature and tapper the charge accordingly. The circuit uses a thermocouple for this function. A second thermocouple nulls out the effects of ambient temperature. The temperature difference between the two thermocouples determines the voltage , which appears at the amplifier's positive input. As battery temperature rises, this small negative voltage ( 1 degree Celcius between the thermocouples equals 40uV ) becomes larger. The amplifier, operating at a gain of 4300, gradually reduces the current through the battery to maintain its inputs at balance. The battery charges at a high rate until heating occurs and the circuit then tapers the charge. The values given in the circuit limit the battery-surface temperature rise over ambient to about 5 Degree Celcius. Part List : Resistor R1_____620K R2_____43K R3_____10R R4_____2K R5_____0.6R 5W Capacitor C1_____1uF C2_____0.1uF Diode D1_____1N4148 D2_____1N4001 Transisto...

Making a Solar Energy Powered an iPhone Battery Charger

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The project was termed as Mighty Minty Boost as it was developed to function as iPod/iPhone charger with solar power. Aside from being small, it has a large battery capacity of 3.7V at 2000mAh and it accepts input power from 3.7V to 7V. As shown in the images below, it can become a compact USB power supply when the solar cell is removed after charging. The Velcro is used to secure the Mighty Minty Boost inside a backpack or messenger bag after unplugging the solar cell. For faster charging, a larger solar cell can be attached to the bag. Enough power can be generated to fully charge an iPhone in about 5.5 hours and an iPod Touch in 4 hours using a slightly larger solar cell with 6V at 250mAh. The charger will automatically switch to trickle charging when the cell reaches full charge. The charging current is limited to 100mA when charging using the mini USB port and the charging is limited to 280mA when charging using the barrel plug jack . The materials needed to build the charger incl...

Automatic 9 volt Battery Charger Circuit Diagram

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Good care given to your NiCad batteries will ensure a long life. However, they do need to be handled and charged with special care. It is therefore important to first discharge the NiCad to 1 Volt per cell, ensure that the battery is discharged, and then start the charge cycle. recommend a charge current of 1/10th the capacity for a duration of about 15 hours uninterrupted. In reality, we learn some hard lessons when we forget to switch the charger off after the 15 hours and find that one or more cells inside the battery no longer accept a charge. That is the very reason that the circuit above is fully automated. The only thing to do is connect the battery and press the 'Start' button. When the discharge cycle is finished the circuit switches over to charge for 15 hours. After the 15 hours the circuits maintains a trickle charge to keep the battery 'topped-up Automatic 9-volt Battery Charger Circuit Diagram Before I go into the schematic details I like to explain some of th...

9V Battery Replacement Power Supply

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This circuit was originally designed to power a motorcycle intercom from the vehicle supply system. This type of intercom, which is used for communication between driver and passenger, generally requires quite a bit of power. In order to improve intelligibility there is often elaborate filtering and a compander is sometimes used as well. The disadvantage is that a battery doesn’t last very long. You could use rechargeable batteries, of course, but that is often rather laborious. It seems much more obvious to use the motorcycle power supply instead. A 9-V converter for such an application has to meet a few special requirements. For one, it has to prevent interference from, for example, the ignition system reaching the attached circuit. It is also preferable that the entire circuit fits in the 9-V battery compartment. This circuit meets these requirements quite successfully and the design has nonetheless remained fairly simple. In the schematic we can recognize a filter, followed by a vo...

Automatic 6 volt 12 volt 24 volt Lead Acid Battery Charger

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A simple yet accurate automatic, regulated 6/12/24 volt lead acid battery charger circuit is explained in this article. The circuit switches off the current to the battery as soon as the battery reaches full charge. An illuminated LED at the output indiacates the fully charged condition of the battery. The circuit diagram may be understood from the following points: Fundamentally the voltage control and regulation is done by the versatile, work horse IC LM 338. An input DC supply volt in the range of 30 is applied to the input of the IC. The voltage may be derived from a transformer, bridge and capacitor network. The value of the 47k  preset is set to get the required output voltage, depending upon the battery voltage to be charged. If a 6 volt battery needs to charged, R2 is selected to produce a voltage of around 7 volts at the output, for a 12 volt battery it becomes 14 volts and for a 24 volt battery, the setting is done at around 28 volts. The above settings take ...

Simple Lead Acid Battery Charger 2

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The above pictured schematic diagram is just a standard constant current model with a added current limiter, consisting of Q1, R1, and R4. The moment too much current is flowing biases Q1 and drops the output voltage. The output voltage is: 1.2 x (P1+R2+R3)/R3 volt. Current limiting kicks in when the current is about 0.6/R1 amp. For a 6-volt battery which requires fast-charging, the charge voltage is 3 x 2.45 = 7.35 V. (3 cells at 2.45v per cell). So the total value for R2 + P1 is then about 585 ohm. For a 12 V battery the value for R2 + P1 is then about 1290 ohm.  For this power supply to work efficiently, the input voltage has to be a minimum of 3V higher than the output voltage. P1 is a standard trimmer potentiometer of sufficient watt for your application. The LM317 must be cooled on a sufficient (large) coolrib. Q1 (BC140) can be replaced with a NTE128 or the older ECG128 (same company). Except as a charger , this circuit can also be used as a regular power supply . Parts ...

LM3914 Based Battery Voltage Monitor

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This voltage monitor is made to display the voltage of 12v battery (for UPS) on LEDs. For this purpose LM3914 is used. The voltage range decided to display is 10v to 13.5v for 12v battery. LM3914 is display driver that can be used in dot  mode or in bar mode; dot mode , with only one led is lit at a time, and in bar mode where it lights leds progressively when the voltage increases. The circuit needs to be powered from the battery being measured and to be able to adjust the lower and upper voltages that light the first and last leds on the led bar. For the 12V battery, the first led in the bar will lit at 10V and the last one at 13.5V , giving 0.35V per led. These thresholds may be set to other values by adjusting two trimmers in the circuit. Calculation and Adjustments: Current flowing per led is controlled by R3 resistor, by applying ohm's law  Ir3 =1.25v/ 4.7kohm =266uA.  Where 1.25v is the minimum voltage required to operate the led. To be able to read the supply vo...

Battery Charger Used in Grid and Substation

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In almost on all the 132 kV & 220 kV Sub-stations two sets of 110 V (for protection) and one set of 48 V (for carrier communication) lead Acid station batteries along with battery chargers are installed. The battery charging equipment comprises of a float charger and a boost charger. Stabilization  output voltage is provided in the float charger to float the battery at the correct level. The battery can be boost charging after a prolonged mains failure by the boost charger. These chargers have been provided protection for under voltage DC & earth fault. DC Board is installed to feed various essential DC load from a separate feeder. Recommended specific gravity of cells at 27 0 C (electrolyte temp) should be 1.210 ± 0.005. Actual temp should be measured in the electrolyte of the cell. If the temp is different than 27 0 C the correction ± 0.0007/ 0 C change in temp. should be made in sp. gr. (Subtract for temp. below 27 0   C  and add f...

Battery Charger LM317

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Lead Acid Battery Charger circuit is highly recommended to recharge battery. And recommended that maximum voltage 24V 7A battery, so you can recharge a battery simultaneously. Battery Charger has been little use of several components such as diodes, electrolytic capacitors , transistors , resistors, and also for strengthening of the voltage and current stresses. And also do not forget to lowering electric voltage 220V to 20V-35V 5-10 Ampere suitable for Lead Acid Battery Charger circuit.  List of components for the circuit Lead Acid battery : R1               = 1 Ω 2w R2               = 100 Ω R3               = 220 Ω R4               = 10K Ω Trim D1 - D5       = IN4004 Q1               = BC547 IC 1          ...

Battery Juicer

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More and more electronic devices are portable and run off batteries . It is no surprise, then, that so many flat batteries find their way into the bin and often far too early. When a set of batteries can no longer run some device for example, a flashgun the cells are not necessarily completely discharged. If you put an apparently unserviceable AA-size cell into a radio-controlled clock with an LCD display it will run for months if not years. Of course not every partially discharged cell can be put in a clock. The circuit presented here lets you squeeze the last Watt-second out of your batteries , providing a bright ‘night light’ - for free! The circuit features a TBA820M, a cheap audio power amplifier capable of operating from a very low supply voltage. Here it is connected as an a stable multivibrator running at a frequency of around 13 kHz. Together with the two diodes and electrolytic capacitor this forms a DC-DC converter which can almost double the voltage from between four and ...

Motorcycle Battery Charger

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Ordinary car battery chargers are simple and inexpensive devices that continuously charge the battery with a pace few amps, for the time the device is ON. If the holder does not close in time the charger, the battery will overcharge and electrowinning capacity will be lost by evaporation or likely to be destroyed elements. The charger circuit overcomes these defects. Electronically controls the battery charge and has a feedback control circuit, causing the battery to charge a maximum rate until fully charged. When fully charged, lights up a red Led (LD2). The charger is designed to charge batteries of 12V, only. What should be paid by whom built the circuit, are the cables connecting the transformer to the circuit and then the battery should be high profile, so that heat when it passes through the current load and also not cause voltage drop in the path of current through them. Motorcycle Battery Charger Circuit Diagram When construction is finished turn the TR1 in place zero valu...

Car Battery 12v Charger Circuit Diagram

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The usual chargers of battery automotive, are simple and cheap appliances that charge continuously the battery, with a rythm of few amperes, for the time where the appliance is ON. If the holder do not close in time the charger, the battery will overcharge and her electrolytic faculty are lost with evaporation or likely exists destruction of her elements. The charger of circuit exceeds these faults. It checks electronic the situation of charge of battery and it has circuit of control with retroaction, that forces the battery charge with biggest rythm until charge completely. When charge completely, it turns on one RED led (LD2). The charger has been drawn in order to charge batteries of 12V, ONLY. What should watch it from what it manufactures the circuit, they are the cables that connect the transformer with the circuit and in the continuity the battery, should they are big cross-section, so that heat when it passes from in them the current of charge and also they do not cause fall of...

Make Your Iphone Battery Last Longer

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I’ve owned a Iphone for a while now, it’s an amazing phone, the best I have ever used so far. But when I first started using it, my only concern was that the battery didn’t last as much as I expected. After two days, it was gone, and when I needed it, the phone just didn’t turn ON. I used to let the wireless on almost all the time and downloading many new apps. Now that I have some more experience on how my little gadget works, I will try to share some ideas on how you can optimize your iphone’s battery life and have a better iExperience. Wireless connectivity will drawn your battery even if you are not using it. Keeping it on, it will always try to connect to some open hot spot, try to check your emails and much more. So a good idea is to turn it on when using, and after, turn it off. Bluetooth have a similar battery usage as Wi-Fi, so there’s not much reason to leave it on if you are not using it (I believe that the most common usage for bluetooth today is the headsets and car kits)....

Battery Charger Using LTC4078

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Using the LTC4078 standalone linear charger circuit you can design a very simple single-cell battery charger circuit for Li-Ion Li-Polymer battery . This LTC4078 battery charger circuit works from both wall adapter and USB inputs. This charger can detect power at the inputs and automatically select the appropriate power source for charging. Battery Charger Using LTC4078 Circuit diagram As you can see in the circuit diagram , this Li-Ion Li-Polymer charger requires few external components and you will need to apply just few equations ,to design a full work USB , wall adapter charger . The charge current can be programmed up to 950mA from wall adapter input . IUSB pin is used for program the charge current for USB power that can be programmed by connecting a resistor to the ground. The voltage on this pin can be used to measure the battery current delivered from the USB input using the following formula: IBAT = (VIUSB/RIUSB)*1000 . ITERM pin is the termination current threshold program t...

Reliable Car Battery Tester

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This circuit uses the popular and easy to find LM3914 IC. This IC is very simple to drive, needs no voltage regulators (it has a built in voltage regulator) and can be powered from almost every source. This circuit is very easy to explain: When the test button is pressed, the Car battery voltage is feed into a high impedance voltage divider. His purpose is to divide 12V to 1,25V (or lower values to lower values). This solution is better than letting the internal voltage regulator set the 12V sample voltage to be feed into the internal voltage divider simply because it cannot regulate 12V when the voltage drops lower (linear regulators only step down). Simply wiring with no adjust, the regulator provides stable 1,25V which is fed into the precision internal resistor cascade to generate sample voltages for the internal comparators. Anyway the default setting let you to measure voltages between 8 and 12V but you can measure even from 0V to 12V setting the offset trimmer to 0 (but i think ...

USB Powered Mobile Phone Battery Charger

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Now you can charge your Mobile Phone from the USB outlet of PC This simple circuit can give regulated 4.7 volts for charging a mobile phone. USB outlet can give 5 volts DC at 100mA current which is sufficient for the slow charging of mobile phones. Most of the Mobile Phone batteries are rated 3.6 volts at 1000 to 1300 mAh. These battery packs have 3 NiMh or Lithium cells having 1.2 volt rating. Usually the battery pack requires 4.5 volts at 300-500 mA current for fast charging. But low current charging is better to increase the efficiency of the battery. The circuit described here provides 4.7 regulated voltage and sufficient current for the slow charging of the mobile phone. Transistor Q1 is used to give the regulated output. Any medium power NPN transistor like CL100, BD139, TIP122 can be used. Zener diode D2 controls the output voltage and D1 protects the polarity of the output supply. Front end of the circuit should be connected to a A type USB plug. Connect a red wire to pin1 and ...

USB Charger For Lithium Ion battery

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USB Battery Charger For Lithium Ion battery with the LM3622 is a series of lithium ion battery charger. This charger circuit operates using power from the USB source PC. Current consumption of a series of USB Battery Charger For Lithium Ion battery with 400mA LM3622 is limited by R1, so it does not exceed the current maximum limit that can be given by a USB computer. Brains from USB Battery Charger For Lithium Ion battery with IC LM3622 , it is a national of having special technical specification charger for lithium ion batteries. In a series of USB Battery Charger For Lithium Ion with LM3622 R1 0.25 Ohm value that serves to limit the charging current 400mA to the battery. Q2 and Q1 is the last part of the USB Battery Charger For Lithium Ion battery with the LM3622. In principle, USB Battery Charger For Lithium Ion with LM3622 identify the condition of the battery full charged battery voltage via pin 6 LM3622. USB Series Lithium Ion Battery Charger For LM3622 is equipped with a switch ...

Simple Mobile Phone Battery Charger

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Mobile phone chargers available in the market are quite expensive. The circuit presented here comes as a low-cost alternative to charge mobile telephones/battery packs with a rating of 7.2 volts, such as Nokia 6110/6150.   Circuit diagram: Mobile Phone Battery Charger Circuit Diagram   Parts R1 = 1K R2 = 47R R3 = 10R R4 = 47R C1 = 1000uF-25V D1 = LEDs any color D2 = LEDs any color D3 = LEDs any color D4 = 1N4007 D5 = 1N4007 IC1 = LM7806 T1 = 9VAC Xformer 250mA BR1 = Diode bridge 1A Circuit Operation: The 220-240V AC mains supply is down-converted to 9V AC by transformer T1. The transformer output is rectified by BR1 and the positive DC supply is directly connected to the charger’s output contact, while the negative terminal is connected through current limiting resistor R2. D2 works as a power indicator with R1 serving as the current limiter and D3 indicates the charging status. During the charging period, about 3 volts drop occurs across R2, which turns on D3 through R3. An e...

Battery Level Indicator 36 Volts Schematic Circuit

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Battery Level Indicator 36 Volts Schematic Circuit Battery Level Indicator 36 Volts Schematic Circuit This battery level indicator offers (5) LEDs that light up progressively as the battery voltage increases. This is a update of the 24V Battery Level Indicator. While designed for 36V systems, it is easily modified to 24V, 48V or 60V simply by changing two resistors. LED Color Charge Level Red: Power Connected (0%) (essentially always on) Orange: Greater than 35V (25%) Yellow: Greater than 37V (50%) Green: Greater than 39V (75%) Blue: Greater than 41V (100%) (full charge is about 41 to 42V) Of course, you may select your own colors if desired. High voltage issues One limiting factor is the LM339 that has an absolute maximum voltage rating of 36V –and it is not good practice to operate near that point. The solution involves running the IC power rail off a zener shunt regulator. Shunt regulators are very simple, inexpensive and robust –good for this application. However, the LM339 ope...

Battery Charger using LM317 Regulator

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Battery Charger using LM317 Regulator This Battery Charger is very similar to the universal charger that uses the constant current load. But this is much simpler to build and can be built using only two parties, the LM317 regulator and resistance. The use of diode D is for protection against short circuits. Capacitors C1 and C2 is good voltage regulation. Resistance R2 operates a dummy load when the battery is disconnected. The idea of ​​this magazine is the output current is equal to 1.2 V, divided by the value of R1. Part List: LM317 R1 - see the values in table below R2 - 2.2 kilo-ohms 1/4W C1,C2 - 47uF/25V, or any value will do, the higher the better D - 1N4001 or any similar diode at-least 1A rated