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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Servicing a Maintenance Free Battery. Start Up Project 29

6BI found that my UPS is not giving sufficient back up as expected for 20 minutes. I thought that I have to spend Rs. 800 to replace the battery. But I was not in a hurry. Want to find out the reason. After 5 minutes, the PC shutdowns. Why so? The UPS battery is not giving sufficient power (Ampere Hour) to run the load. The UPS battery is a 12 volt 7 Ah (Ampere hour) Maintenance free Sealed LeadAcid battery (SLA). That means, it is “Maintenance free” and can be used for long time without any attention. But what happens is, the cells dry out due to heat generation. This happens after 6 months to 1 year of use . It is a Lead Acid battery that requires Electrolyte in the cells. So water is necessary inside. It has 6 individual cells giving 2V each. After removing the battery from the UPS, I found that it is very easy to rejuvenate the battery through “Hydration”. The battery will become top, if the dry cells are filled with battery water. Hydrated the battery and charged. Well, now it is giving more than 15 minutes back up. Saved Rs. 800 and reduced an e-waste. You can also rejuvenate the 6V Emergency lamp battery like this. So do it yourself. It is only a 10 minutes job.

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Peltier Fridge. Start Up Project 27

OAWow! We can make a cup of cold water in 5 minutes without a Fridge. You need only a Peltier Element, a 12 volt high current battery and a Computer cooling fan. Peltier element is a semiconductor plate like device with Cold and Hot sides. When we provide 12 -18V, 1 amps power to it, one side of the Peltier suddenly cools and the other side turns hot. The cool side temperature goes down below 0 degree and the hot side becomes around 100 degree. So to transfer that much heat, the Peltier should be placed over a large Heat sink. A Computer cooling fan with heat sink is the best choice. Fan will remove the heat from the Peltier and heat sink. At the same time, the cold side turns too cool in minutes. Without a heat sink, the Peltier will be damaged. If we reverse the Polarity (+ and ) of the power supply to Peltier, the sides reverses. That means, cool side becomes hot side and vice versa. Let us make one Peltier Fridge  to get some cold water. Later we can change it as a heater to drink hot water. Peltier costs around Rs.200.
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Portable Bread Board Power Supply. Start Up Project 21

5AYou can carry this Portable bread board power supply to do electronics work outdoor. Keep this in your bag along with some components so that you can enjoy the holidays with the fun of electronics. This Mini bread board is powered by a 3 volt Lithium cell.  A DC-DC booster Module converts the 3V to 5.1V for the Bread board. You can also enjoy  Music from MP3 player, or even charge your Mobile Phone from the Power supply. So make this three in one power supply. Its cost is Rs.150.
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Neodymium Magnet Idea 2. Start Up Project 10

15AYour friends will wonder when they see a Computer Fan lighting an LED by generating Free electricity. Do you believe, the Computer Fan generates electricity when it rotates? Definitely very minute voltage of less than 1 volt is generating at full speed. But it is not sufficient to light an LED. So what happens when some Neodymium Magnets are placed on the Computer fan? Nothing happens specially because the Computer fan has 4 Electromagnets that become magnets only when we give 12 volt DC to it. So the Neodymium magnets are simply  resting on the Computer Fan without doing anything. So let us do one Magic to trick your friends. Don’t forget to the reveal the trick after showing it because it is bad to fool others
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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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DS 18B20 Digital Temperature Sensor. Component Guide 9

DS-18B-20 DS 18B20 is a Programmable Digital Temperature sensor that gives Digital outputs based on the temperature. It provides 9-12 configurable Bit temperature readings which indicate the temperature of the device. Information is sent to / from to connect from a Central Microprocessor to the DS 18B20. Power for reading, writing and temperature conversion can be derived from the Data line itself so that no external power source is needed.
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