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I want to use a Lithium Ion Battery. I saw that there is also a different kind of chargers like Adafruit Micro Lipo/MicroUSB or Adafruit Micro USB Lipo for this kind of battery, do I need it? Can I charge my battery direct from a voltage source?

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    \$\begingroup\$ No, you can't charge directly from a voltage source. When lithium batteries first appeared, it was discovered that letting them float at 4.2V for a long time would eventually cause some of them to fail. When they do fail, they may vent gas violently, catch on fire, and even cause injury or property damage. The standard way to charge a Lion battery is CC followed by CV with current monitoring. Once the charge current drops to some low level, charge should be terminated. If charge current does not drop after a few hours terminate anyway. And in this case the battery may be bad. \$\endgroup\$
    – user57037
    Dec 22, 2015 at 17:37

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As mkeith mentioned in a comment, the charging starts out as CC (constant current) followed by CV (constant voltage). This is what the charging profile looks like:

enter image description here

The charging rate is noted as 1C, which just means the charge current is initially equal to the capacity of the battery for one hour, i.e. 1.5 A for a 1500 mAh battery.

If you are buying a stand-alone charger, then you need to buy one specially made for Li-Ion batteries, such as the ones you found. If you are building your own circuit to charge a Li-Ion battery, you need to buy a battery management IC.

There are not too many that come in hobbyist friendly through-hole packages. One that does is the BQ2000 which comes in an 8-pin DIP package. It automatically detects the battery chemistry, and will work with nickel cadmium (NiCd), nickel metal-hydride (NiMH), or lithium-ion (Li-Ion). It's available from Digi-Key for $3.46.

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The answer is: yes, you should use a suitable battery charger. There are different issues regarding the safety of such batteries.

One is for example, the temperature control during charging. These batteries can explode if mishandling.

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