How to determine the voltage level in Lithium Ion battery

Lithium Ion batteries are now widely used in Mobile phones, Power banks, Digital cameras and other devices that requires 3.6 V . Lithium Ion batteries are long lasting since its current rating is very high above 2300 mAh.It is very important to maintain Lithium Ion batteries since, both over charging and poor charging may completely destroy the battery.Some have the habit of plugging the Mobile phone in charger overnight. Mobile battery needs to be charged only when its charge goes below 50 %.Proper charging and discharging increases the life of Mobile battery and its efficiency. Let us see its voltage levels
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Mobile Scanner. Start Up Project 35

2AKeep this Match box size Mobile Scanner in your pocket. It will Scan around you and beeps loudly when a Mobile phone turns active in your vicinity. It can detect the activation of Mobile phone around 2 Meters radius. It beeps during incoming call, outgoing call and when somebody tries to take your Photo. It is an ideal device to detect Mobile phone use in examinations halls, confidential rooms, hospitals etc where Mobile phone is strictly prohibited. Its range can be from 50 cm to 3 meters depending on the type of the active Mobile phone. With  Smart phones, its range is less than 1 meter because there is a mechanism in it to prevent excess radiation. But in ordinary Mobile phones, its range can be up to three meters. Try this nice weekend project.
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USB Wall Socket. Start Up Project 34

15AI have many devices using USB Port for charging. For this, I purchased one USB Hub to connect 4 devices at a time. But the result was disappointing . The devices are not charging and even a Pen drive is not opening in the Hub. Analyzed the reason and found that the USB port of Laptop is not giving sufficient current to the devices for charging. The USB.2.0 Port can give maximum 200 mA current and USB.3.0 can give maximum 400 mA current. Then how all these 4 devices in the Hub charge normally. The 200 mA current from the Laptop port is sharing to all devices, so no one is charging. Moreover, the Laptop gave a warning that, “USB Port over loaded and shutting down”. Remembered that famous saying “Every problem born with its own solution”. Got the remedy. If the current to the USB Hub is increased, all devices will charge normally. But in that case, Laptop is not useful and I have to make a separate power supply. So made a USB Wall socket. It has an AC socket for charging Laptop, and a 5V, 1 Amps SMPS power supply to power the USB hub. Thus the problem solved. The USB Wall socket is fixed on the wall and powered from Mains. SMPS has well AC-DC isolation, so no shock hazard while charging the USB devices. I found the same type of USB Wall socket in the Online shop but its cost is Rs.2500. I made it at the cost of Rs.250. Let us check it.
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Portable Mobile Charger. Start Up Project 14

2AWhy going for a costly Power Bank to charge Mobile Phone? Just use a 9V battery and a few components to make a Portable Mobile charger. Its cost is just Rs.25 and if you use a Rechargeable 9V battery, it can be used up to three years. The Mobile phone battery is a high efficient long lasting Lithium Ion battery that has thousands of charge / discharge cycles. It requires 4 -6 volt DC for charging and the charging current can be between 200- 400 mA. We can drop the 9V from the battery to 6 volt using a Voltage regulator. That’s all. Make it and enjoy the satisfaction of a project building.
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Boost Charger for Mobile Phone Battery. Start Up Project 13.

A1Why allowing Mobile Phone battery for a “Deep Sleep”. Many times we replace the Mobile battery without knowing this Deep sleep property of the battery. Actually the battery is good and we can easily revive the battery from deep sleep just giving a “Shock”. The trick is very simple and you can use the battery again. How the Mobile battery enters into deep sleep? In the Mobile phone battery, there are three pins to connect the battery. One is Positive and the second one is Negative for charging. Then why a third pin? It is known as BSI Pin (Battery Status Indicator). If we are not properly charging or leaving the battery unattended for long time, the Mobile phone will not detect the battery for charging. So by removing the battery and giving a “Boost pulse”, the battery will “Wake up” from sleep and starts charging. Best trick. You need only an USB cable and two pins. You save 350 -500 Rupees. Let us learn the trick.
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Neodymium Magnet Idea 1. Start Up Project 9

NEODYMIUM-MAGNETHow many Neodymium Magnets are resting in your Junk box without any job. Give some job to them. It is fun to use the Neodymium magnets for alternate jobs. You can make a 12 volt power supply and a 6 volt Emergency Mobile Charger with the assistance of Neodymium Magnets. Let us start.
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Portable Power Bank. Home Utility Circuit 11

downloadHere is a simple Portable Power Bank that finds many uses. It can be used as a Portable Mobile Charger or it can be used for powering the bread board projects and so many applications that requires 5V Regulated DC. Let us make it.
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