Technical (टेक्निकल)

Difficulty Rating: 5/10 Abstract: This project gives an overview of the Sealed Maintenance-Free (SMF) Lead-Acid Rechargeable Battery charger using 3-pin  IC LM-317 as voltage regulator and opamp IC LM-324. In case of a simple battery charger, when the battery is fully charged and is left plugged in for more than a day or two, the battery may get damaged. In order to protect the battery from this major risk, the proposed battery charger is designed in such a way that the charging current falls gradually as the charging progresses. So the battery can be left plugged into this charger indefinitely, and it won't bother it in the slightest. Designing the Circuit:   Click the image to view the enlarged version The LM317 is an adjustable three-terminal positive-voltage regulator capable of supplying more than 1.5A over an output-voltage range of 1.25 V to 37 V. It is exceptionally easy to use and requires only two external resistors, R 2 ’ and R 2 ”  (R 2 ...

A device that comes in handy during Mountaineering/Trekking Difficulty Rating: 3/10 Motivation: Using AA pencil cell to power a torch is too mainstream & also power consuming. And if you are a Mountaineer, where torch-light is vital, replacing these cells becomes too much of pain in the ass. Instead, how about a torch which doesn't need cell replacement in the first place?? The chargeable torch-lights (china made), like this one, have become a commonplace in today's Electronics market. Commercial Torch-light (Not mine) But does anyone have a similar torchlight, which has lasted more than a year? So I decided to make one for myself, owing to its use during one of the Mountaineering adventures. My prototype It works just fine !!!!! Hardware: A small pipe, wheel, Long screw (for charging purpose), lots of duct tape, white paper (behind LED) Electronics: 4.8V Li-ion battery, Toggle switch, push-button switch, 9 high-power LED, Dynamo, PCB, 2 Capaci...

Difficulty Rating: 4/10 Exactly 5 months after my Internship/project  at M.A.P.L. Pune, on Lead acid SMF Battery charger,  my knowledge on Battery charging was put to test by a Mechanical Engineering friend. I was asked to charge a 12V 1200mAh NiMh battery. Now, before getting into its technical aspects, a little overview about battery chargers. General battery charging techniques- Trickle chargers This charger provides a constant charge rate of ~ 0.1C. The general idea behind keeping the charge rate low is to compensate for the batteries self-discharge. The charge rate being low, the battery can be left unplugged for days!!!The charge rate of the battery should be equal to self-discharge of the battery. Such chargers are generally used in industrial applications , where less of human intervention is required. Float chargers The battery and the load are constantly connected to the source. The float chargers maintains full charge & provides a protection against...