Charging time for 26650 batteries

[FastNick]

Howdy y'all,

My first post here so here I go. I bought yesterday a mech mod who uses 26650 batteries. I'm a truck driver and I kinda dislike changing batteries often while driving so I figured the 26650 will last more than my regular 18650.
Now I use an Intellicharger I4 and the batteries never reach the maximum charge.
Am I doing something wrong ?
What should be the time for fully charge a 26650 battery?
Thanx

 

[nyiddle]

What do you mean they "never reach maximum charge"? It's very important that in a charge cycle, you actually charge your battery up ALL the way. Taking it off the charger in advance will negatively impact battery longevity and reliability.

A 26650 battery tends to take 3-6 hours to charge (from 3.7v) on a 1A charger. I'm not 100% but I think the i4 only charges at .5A. If you think your battery is being "overcharged" (if you think it's at full, but the charger is still charging it) use a DMM (digital multimeter) and measure the nominal voltage of your battery (very easy to do). If it's not at max voltage, then you should leave it on the charger. If it IS at max voltage, but the charger is still charging it, you have a bad charger.

Again, don't prematurely take your batteries off the charger. Once it goes on the charger, it has to stay until it completes its charge.

 

[Kaezziel]

i4 Intellicharger Specifications
Input: AC 100-240V 50/60Hz 0.35A(MAX) or DC 12V 1A
Output voltage: 4.2V ±1% / 1.48V ±1%
Output current: 375mA × 4 / 750mA × 2
Dimensions: 138mm × 95mm × 36mm
Weight: 184g (without batteries and power cord)
Compatible with:
Li-ion / IMR: 26650, 22650, 18650, 17670, 18490, 17500, 18350,
16340(RCR123), 14500, 10440
Ni-MH / Ni-Cd: AA, AAA, AAAA, C

That means that it provides 750mA per hour to the battery if you are charging 1-2 batteries and 375mA per hour if charging 3-4 batteries.
A little math can tell you how long the charge should take...
A 4200mAh 26650 battery would take around 5.6 hours to charge. 4200/750=5.6
That would be true if you were charging 1 in bay 1 and 1 in bay 3... or just one by itself... if you were charging 3-4 batteries it would take around 11.2 hours. 4200/375=11.2

 

[Topwater Elvis]

What is the battery's voltage when you put them on the charger and when you take them off?
Using a mechanical you need to monitor battery voltage with a multimeter/dvom as the battery is being discharged until you gain the experience to be able to tell when charging is needed. Also use the dvom to measure the resistance of the coils used and to check for shorts in coil & connection points.
An overly discharged battery may never fully recover.

Charging time is dependent on the state of battery discharge & the charge rate of the charger used.
The charge rate specs on the I4 I have show 375ma x4 ~ 750ma x2, a high mah & amp battery drained to 3.4 is gonna take quite some time to charge.

 

[FastNick]

What I mean is that the 26650 never reach the three solid yellow lights on the charger while charging. Even tho they've been in the charger for over 14 hours now.
The 18650 when really low they need about 4 hours and the three solid lights are ON so I take them out from the charger.

 

[nyiddle]

What I mean is that the 26650 never reach the three solid yellow lights on the charger while charging. Even tho they've been in the charger for over 14 hours now.

That's not right. Pull the batteries off the charger and use a multi-meter. Don't use the batteries until you do.

If you're dealing with some overcharged 26650 cells, things could get pretty sketchy pretty fast.

 

[edyle]

What I mean is that the 26650 never reach the three solid yellow lights on the charger while charging. Even tho they've been in the charger for over 14 hours now.
The 18650 when really low they need about 4 hours and the three solid lights are ON so I take them out from the charger.

Are you charging 4 batteries at the same time?
If so maybe it's slower charging multiple batteries.

 

[Topwater Elvis]

Sounds like they've been over discharged & are damaged.
Slim chance your charger is malfunctioning. No way to tell either without a multimeter /dvom.

What voltage are they when you put them on the charger?
How low is really low?
You will ruin batteries by over discharging them.

 

[Kaezziel]

I've got KeepPower 4200mAh batteries and the i4 charger... it eventually charges and lights up all of the lights, but sometimes it seems to take a long time... (I've never timed it to see just how long, but definitely much longer than 18650s, obviously).

I would take the suggestion that others have made and check the voltage with a meter after taking it off of the charger. It should read around 4.2VDC...

 

[FastNick]

I'm not sure why my previous post didn't show up but anyway I'll say it again.
I measured the voltage with the DMM and it shows 4.01 Volts. Then I measured one 18650 charged and it shows 4.14 Volts.
I'm not sure what the heck

 

[FastNick]

Either I'm to newby on this forum and I don't know how to post a message either something is weird because I posted 3 messages and only one is showing up.

Anyway, something is wrong because I have more juice (strength) in the 18650 than in the new 26650.

 

[Kaezziel]

I'm not sure why my previous post didn't show up but anyway I'll say it again.
I measured the voltage with the DMM and it shows 4.01 Volts. Then I measured one 18650 charged and it shows 4.14 Volts.
I'm not sure what the heck

Looks like everything is fine, then... just need to leave the 26650 on charge a little longer. It should eventually light up the third bar on the charger... the Nitecore charger is pretty solid, but it does charge slower than some other chargers out there.... personally, I prefer a slower charge (it's easier on the battery).

 

[nyiddle]

I'm not sure why my previous post didn't show up but anyway I'll say it again.
I measured the voltage with the DMM and it shows 4.01 Volts.

This was the 26650? It's possible your charger is working fine (and your battery) and that you just haven't waited long enough. If the nominal voltage was higher than 4.2, I'd be concerned. At 4.01 though you haven't hit the max nominal voltage. I'd say leave it on the charger for another half hour to hour, check the voltage again.

Then I measured one 18650 charged and it shows 4.14 Volts.

Did your charger say this battery was fully charged?

 

[Poisontail]

Are you charging then at 3.6 volts? Can you change your amp charge? Is it cold?

 

[Kaezziel]

Are you charging then at 3.6 volts? Can you change your amp charge? Is it cold?

There are no adjustments on the intellichargers... plug it into the wall, put a battery in it and wait for it to finish...
Good point on the temp question, though... that can make a difference on charge times...

 

[FastNick]

One of the two 26650 I bought was still in the charger while I started the thread and few seconds ago I've seen the third light came to solid. I was so happy that finally have one fully charged. But the result is the same as I stated above.
There is not enough juice in the battery compared with my 18650. How that can be ?

Now I read on the back of my SYSMAX Nitecore Intellicharger i4 : compatible with : 18650,17670,18490, 17500, 17335, 16340 (RCR123), 14500, 10440
So there is nowhere 26650. What the heck i4 is this. On the website says it is compatible with 26650 but on my i4 it doesn't.

 

[Kaezziel]

One of the two 26650 I bought was still in the charger while I started the thread and few seconds ago I've seen the third light came to solid. I was so happy that finally have one fully charged. But the result is the same as I stated above.
There is not enough juice in the battery compared with my 18650. How that can be ?

Now I read on the back of my SYSMAX Nitecore Intellicharger i4 : compatible with : 18650,17670,18490, 17500, 17335, 16340 (RCR123), 14500, 10440
So there is nowhere 26650. What the heck i4 is this. On the website says it is compatible with 26650 but on my i4 it doesn't.

I don't know... I have the "updated" i4... it states on the box that it is compatible with 26650...

 

[FastNick]

Anyway, thanx for all the input. It looks like the charger is not up to the requested job. I'll buy another one.

 

[Poisontail]

There are no adjustments on the intellichargers... plug it into the wall, put a battery in it and wait for it to finish...
Good point on the temp question, though... that can make a difference on charge times...

Get the xtar vp2 I friggin love it!

 

[Kaezziel]

I've heard that the Xtar charger is pretty good... I have no personal experience with it though...
Sorry that things aren't working out for you, Nick... hopefully things will work out with the new charger...