amps and batteries

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im_coryy

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so im reading a wonderful article about battery safety

http://www.e-cigarette-forum.com/fo...scussion/355443-read-batteries-explained.html

and as i was reading i cam across something interesting, "Always use the proper charger for your battery. Ensure that the output voltage and amperage of the charger match or are lower than that of the battery going to be charged. Charging a battery at a LOWER amp rating than listed will not harm it and only causes your charge time to increase. Charging a battery at a HIGHER amp rating than listed however can result in a fire hazard.

Remember, just because a battery fits into a charger, doesn't mean the battery is SAFE in that charger!

How do I find out the Amps I can charge my battery at?

There is a very simple way to calculate the amp output needed to properly charge your battery. Remember, your charge should never exceed (small margins can be acceptable) the max amp rating. You simply take the mah rating of your battery and move the decimal 3 spots to the left. For example:

3500 mah battery = 3.5 amp MAX
2250 mah battery = 2.25 amp MAX
600 mah battery = 0.6 amp MAX"

well i just recently bought some batterie and a charger, i bought this...

Xtar WP2 II - Battery Chargers
and these batteries

Sony US18650VTC5 2600mAh 30 amp

i figured out it would be 2.6 amps but my question is this safe? i honeslt dont know i tried to find an amp limit i couldnt find one, when charging a battery dont i just watch for the volts? 4.2 volts and were good to go and you pop it back on the charger once it hits 3.5 right?
 

GeorgeWachsmuth

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Model: Sony US18650VTC5 lithium ion high power cell
2. Nominal capacity: 2600mAh
3. Rated capacity: 2500mAh
4. Nominal voltage: 3.6V
5. Charge voltage: 4.20±0.05V
6. Cut-off voltage: 2.5V
7. Max. charge voltage: 4.25V
8. Continuous maximum charge current: 4A
9. Continuous plus discharge current: 12A
10. Continuous maximum discharge current: 30A
 
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The Vagabond

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Sep 15, 2013
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Model: Sony US18650VTC5 lithium ion high power cell
2. Nominal capacity: 2600mAh
3. Rated capacity: 2500mAh
4. Nominal voltage: 3.6V
5. Charge voltage: 4.20±0.05V
6. Cut-off voltage: 2.5V
7. Max. charge voltage: 4.25V
8. Continuous maximum charge current: 4A
9. Continuous plus discharge current: 12A
10. Continuous maximum discharge current: 30A

I am concerned about 9 &10 I think they are reversed and should be
9. Continuous pulse discharge current: 30A
10. Continuous maximum discharge current: 12A
but I could be mistaken
 

Ryedan

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Mar 31, 2012
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How do I find out the Amps I can charge my battery at?

There is a very simple way to calculate the amp output needed to properly charge your battery. Remember, your charge should never exceed (small margins can be acceptable) the max amp rating. You simply take the mah rating of your battery and move the decimal 3 spots to the left. For example:

3500 mah battery = 3.5 amp MAX
2250 mah battery = 2.25 amp MAX
600 mah battery = 0.6 amp MAX"

well i just recently bought some batterie and a charger, i bought this...

[/B]Xtar WP2 II - Battery Chargers
and these batteries

Sony US18650VTC5 2600mAh 30 amp

i figured out it would be 2.6 amps but my question is this safe? i honeslt dont know i tried to find an amp limit i couldnt find one, when charging a battery dont i just watch for the volts? 4.2 volts and were good to go and you pop it back on the charger once it hits 3.5 right?

You're going to be perfectly fine with that battery and charger. Yes, with IMR or hybrid Li-ion batteries you can typically safely charge them at at least their mAh rating in amps. That's the same as what you did above; 2600 mAh (miliamp hours) equals 2.6 Ah (amp hours) and can be safely charged at 2.6A. It is better though to find the actual specification just in case. ICR Li-ion batteries sometimes have a lower max amp charge spec.

I actually have that charger and Sony VTC3 and VTC4 batteries so I'm pretty familiar with them. Here are the VTC5 batteries at Illumination Supply. Standard charge current is listed as 2.5A. There is also a quick charge current they do not list that's higher. The WP2 charger gives you the option to charge at 0.5A or 1.0A, so you're not even close to the limit at the highest setting.

The maximum continuous discharge current is 30A. The max pulse discharge is not listed, but I'm pretty sure it's 60A like the VTC4.

When the charger stops charging the battery should be 4.2V +-0.05V, so 4.15 - 4.25V. Mine leaves the batteries at about 4.21V, but that could be just that my DMM is a bit off. After 1/2 an hour of rest the voltage drops to about 4.19V. This is normal. My WP2 warms up a bit charging at 1A which is also normal. The battery itself should not warm up.

If you're using the battery in a regulated device like a Vamo or Provari, you can use it until the device signals low battery. In a mechanical mod you should monitor voltage as it drains until you know what around 3.7V vapes like. I use mech mods all the time and I typically catch the battery fall off at between 3.8 and 3.65V. I will replace the battery in that range. You can go lower to say 3.5V as you said if you feel like, but after you pass 3.6V the voltage drops faster and faster and it can get tricky to catch it before it gets too low. IMO it's good to consider 3.0V an absolute minimum, but I have taken mine down to 2.5V a couple of times by mistake at the beginning and had no problems with them. Do that too often though and their life span decreases.

Charging more often increases the number of charge cycles you'll get from the battery so you do not lose any life, nor do Li-ion develop memory. Charging more often is a good deal all around, specially in a mechanical mod.

Hope this helps.
 
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