Charging 18650's recommended charging current?

[tjeco]

I use a pair of AWT 35A and Smurfs 18650's, and i always prefer to charge them slowly at 0.5A, is that safer as compared to charging them at 1A? If I were given a choice I would have charge them at 0.25A.

So is charging at lower Amperes affect the batteries performance and relatively safer? And is there any benefit in charging slowly?
And I only charge my batteries overnight so I really don't mind the slow charge.

Thanks guys!

 

[Mooch]

Slower = cooler = longer battery life

For the higher current batteries, 15A-rated and above, you really aren't going to see much of a difference in battery life between charging at 0.5A and 0.25A. But, it won't hurt anything to charge at the lower rate. Let the battery temperature be your guide. If any battery gets more than warm, lower the charge rate.

Having a charger that doesn't turn off when done can hurt your batteries though.

 

[Robert Cromwell]

Probably no difference in safety but the slower charge should be easier on them and maker them last a bit longer.

 

[SpaceApe]

As many others have previously stated lower charging amperage means less strain on the battery which in return prolongs battery life. Below .5A there is such a minor difference in battery temperature while charging that I'm not sure the extension of the batteries lifespan justifies the extended charging time. Looks like I have an experiment to conduct...

 

[ReigntheGamer]

If I have a ton of time to charge, .25A. If I need them ready yesterday, 1.00A.

 

[bussdriver]

Good rule of thumb if you have a choice of charge currents is to charged them at about 0.5C max. Batteries charged at or above 1C may suffer in lifespan due to heat buildup, not to mention 'Let's keep it safe'.

For a 700 mah battery, no more than 350 ma charge current.
For a 2000 mah battery, no more than 1 amp charge current
For a 5000 mah battery, no more than 2.5 amp charge current.

 

[bluecat]

I always thought (There I go thinking again) that each battery had a recommended charge rate. The slower the charge the longer the cell would last. Take this for example

AW IMR 18650 3.7v 3000mAh Flat Top

This part in particular

Standard Charge Rate: CC/CV ( 1.5A - 4A max.)

It would lead me to believe that any charging between 1.5A and 4A is "safe". Maybe I misunderstood?

BTW.. nice battery there.

 

[Mooch]

I always thought (There I go thinking again) that each battery had a recommended charge rate. The slower the charge the longer the cell would last. Take this for example

AW IMR 18650 3.7v 3000mAh Flat Top

This part in particular

Standard Charge Rate: CC/CV ( 1.5A - 4A max.)

It would lead me to believe that any charging between 1.5A and 4A is "safe". Maybe I misunderstood?

BTW.. nice battery there.

It would be safe but the battery will have a longer life if you charge at the lower end of that 1.5A-4A range as that lowers the temperature the battery reaches during charging. I'm thinking that 1.5A is the "standard" rate and 4A is what is often called the "fast" charge rate by battery manufacturers.

 

[bluecat]

Danke, mate.

 

[bussdriver]

3000 mah x 0.5 = 1500 ma, or 1.5 amps.

Again, 0.5C max. For a standard charge. For maximum life. For maximum safety.

It's sometimes necessary to come up with a safe 'standard', considering the many claims that can be made by peddlers. Lithium battery technology is at a particular point, no matter what many may claim. There is no super battery yet, only derivations of the standards; but no magic bullet yet.

Using the 0.5C method will ensure that you are always safe, and always treating your batteries with the utmost in charging 'respect'.

 

[bluecat]

Aye mate and thanks. I guess I forgot what the .5C was. The 4 amp charging is what I see more of.

 

[Hans Wermhat]

My Luc charger has a 2A setting. It's all I use. My batteries never get more than slightly warm. My first pair of VTC4's are about 9 months old now and still work like new.

 

[IMFire3605]

I've found not only is a low current trickle charge easier on a battery, at the .25 to .5amp charge rate, the battery generally charges up closer to full capacity and lasts longer on a charge then. I however have well over a dozen batteries, battery first comes out of my device, set it aside for about 6 to 8 hours, then charge it, once charging done, goes into another 4 to 8 hour set time before goes into my ready to use sets. If you have few batteries and are discharging them at a rate of 1 an hour, then I can see bumping charging current up to keep your rotation going, but would suggest getting more batteries, as the two set aside times I use allows the batteries to cool fully before charge or use, and lets the ions in the battery come to relative rest and not be agitated continuously

 

[Robert Cromwell]

I always thought (There I go thinking again) that each battery had a recommended charge rate. The slower the charge the longer the cell would last. Take this for example

AW IMR 18650 3.7v 3000mAh Flat Top

This part in particular

Standard Charge Rate: CC/CV ( 1.5A - 4A max.)

It would lead me to believe that any charging between 1.5A and 4A is "safe". Maybe I misunderstood?

BTW.. nice battery there.

A tem sensor is required to reduce charging current if the battery gets too warm at a 4 amp rate.