Charger Definition and 107 Threads

A battery charger, or recharger, is a device used to put energy into a secondary cell or rechargeable battery by forcing an electric current through it.
The charging protocol (how much voltage or current for how long, and what to do when charging is complete, for instance) depends on the size and type of the battery being charged. Some battery types have high tolerance for overcharging (i.e., continued charging after the battery has been fully charged) and can be recharged by connection to a constant voltage source or a constant current source, depending on battery type. Simple chargers of this type must be manually disconnected at the end of the charge cycle, and some battery types absolutely require, or may use, a timer to cut off charging current at some fixed time, approximately when charging is complete. Other battery types cannot withstand over-charging, becoming damaged (reduced capacity, reduced lifetime), over heating or even exploding.
The charger may have temperature or voltage sensing circuits and a microprocessor controller to safely adjust the charging current and voltage, determine the state of charge, and cut off at the end of charge.
A trickle charger provides a relatively small amount of current, only enough to counteract self-discharge of a battery that is idle for a long time. Some battery types cannot tolerate trickle charging of any kind; attempts to do so may result in damage. Lithium ion battery cells use a chemistry system which does not permit indefinite trickle charging.Slow battery chargers may take several hours to complete a charge. High-rate chargers may restore most capacity much faster, but high rate chargers can be more than some battery types can tolerate. Such batteries require active monitoring of the battery to protect it from overcharging. Electric vehicles ideally need high-rate chargers. For public access, installation of such chargers and the distribution support for them is an issue in the proposed adoption of electric cars.

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  1. G

    Solar Panel Charger Project: How Do Modern Smart Chargers Work?

    The Maker Greetings, I saw a slew of discount solar panels and I want to use one to power my iPhone or possibly netbook. I’ve researched this but it seems the more I learn the more I realize how little I actually know. There appears to be a wide variety of charging circuits and methods...
  2. A

    Why does this NiMH solar charger work?

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  3. M

    How Does a Battery Charger Work and What Causes Overcharging?

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  4. R

    Understanding Charger Circuits and Diode Voltage Drop

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  5. B

    Why Phone Charger Makes High Frequency Sound

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  6. R

    Why Is My Emergency Phone Charger Draining My Battery?

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  7. R

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  8. Z

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  9. M

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  10. M

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  11. O

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  12. G

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  13. L

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  14. F

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  15. O

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  16. V

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  17. F

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  18. J

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  19. K

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  20. A

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  21. E

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  22. K

    How Effective Is an LM317 in Sequentially Charging Multiple Batteries?

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  23. M

    Too Long on the Battery Charger

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  24. D

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  25. S

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  26. A

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  27. R

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  28. N

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  29. zoobyshoe

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  30. G

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  31. N

    AC Battery Charger: Exploring its Effectiveness for Charging Batteries

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  32. O

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  33. 0

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  34. K

    How does a battery charger work?

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  35. V

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  36. A

    Capacitor Charger | LED Illuminate when Complete

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  37. B

    How Do NIMH Chargers Detect End of Charge?

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  38. U

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  39. S

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  40. U

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  41. D

    What are the best settings for charging a 24v 12ah Lead Acid Battery?

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  42. B

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  43. S

    Which Laptop Charger is More Efficient for a 65W Rated Laptop?

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  44. M

    Old Battery Charger for RC Car in Wichita KS - Can it Charge Ni-H Batteries?

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  45. S

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  46. N

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  47. J

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  48. Z

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  49. N

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  50. ranger

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