king kong icr 26650 only charged to 4.2v

Hi all

Just got a King Kong ICR 26650 and an xtar sp1 charger from mtnelectronics.

I set the charger at the 4.35v charge mode but when all was said and done, my volt meter still measured 4.2v.

Good enough, or I’m doing something wrong?


King Kong ICR 26650 is 4,2V cell, not 4,35V!!!

Well, that explains it. Is the inr version the 4.35v one?


charging a 4.2v cell to 4.35 is asking for severely shortened lifespan at the least and catastropic failure at the worst.
dont do that!

Well, the charger wouldn’t let me do it anyway. I could have sworn the king kongs go to 4.35v.

Which 26650s are capable of that voltage?

Not a big deal…. My convoy x3 with the king kong could double as a search and rescue spot light. Serious throw!


There are no 26650s which can be charged to 4.35V….or at least there are no which are specified to do that…

I can’t think of any 26650 batteries that go to 4.35 volts, i’ve got some Kongs and they certainly don’t
What makes you think they should be 4.35 volts? if it’s on a website listing it’s wrong
I know on the fasteck website there is some confusion over the chemistry and a few post about it on their q and a pages

I thought I read about charging to 4.35v in this forum.

Well, more kudos to the xtar sp1 charger. It wouldn’t let me turn the king Kong into a grenade :wink:

Preface: right, there are no 4.35v 26650 cells. Don’t try charging to 4.35v.

That said, are you sure that the charger didn’t take the cell up to 4.35v and terminate and then and then the cell settled back down? (That’s still very bad. I just am not aware of any safety feature which would allow the charger to detect a 4.2v cell and prevent charging to 4.35v.)

I measured the cell right off the charger. The cell barely got warm to the touch in the sp1.

Oh well, lesson learned. 4.2v from now on :slight_smile:


Was the KK a protected cell?In that case,over voltage protection would kick in.

Good point, but doesn’t OVP normally kick in around 4.25v-4.30v?

Don’t assume you did no damage. “What, me worry?” isn’t the right attitude with lithium-ions.
You can’t trust that the equipment has protected you from the consequences of making mistakes.
Damage to lithium-ions is not immediately apparent.
You should know about this.
Do you understand how crystal growth is initiated, and then how long it can go on quietly before the membrane gets damaged inside, once the crystal growth starts?

As Wight said above:

If there is such a safety feature, it will be worth knowing about. You might look for HKJ’s review of that charger and inquire.

4.25+/-0.05v can get 4.20v,but it feels a bit too convenient.

is the best news,but I don’t know nearly enough about silent cell degradation :open_mouth: for that to be really reassuring.

Okay, maybe I didn’t overcharge the battery.

Trying to understand the instructions for the xtar sp1.

There’s a switch on the side for .5a (3.2v), 1a(3.6v) and 2a(3.8v).

But then there’s also a button on top to toggle between the 3 settings as well. What’s the difference?

I bought the charger to charge the 26650 at 2a. That’s half the 4000+mah , so should be fine.

So, how do you charge at 2a and terminate at 4.2v ? I’m thinking the charger decides whether to give you 4.2 or 4.35?


I’ll put my earlier statement in more concrete terms: The charger cannot detect 4.2/4.35v for you.


I don’t understand where you are getting the bolded part from. All the resources I’ve looked at clearly mark the voltage switch on the side as voltage only. It’s “3.2/3.6/3.8”, there is no marking on the side which indicates charge current. Can you post a picture of instructions showing otherwise maybe?

Nevermind. I see that you are confused by the indicator LEDs. Please read HKJ’s review. HKJ explains how the indicator LEDs work. HKJ - Charger Xtar SP1

Still confused. Yes, no current markings on the side switch. But there’s current and voltage on the top led indicators where you can toggle with the button.

It sounds like select 3.6v on the side switch and 2a on the led on the top. But under the 2a led, it also says 3.8v (and 3.6v for 1a and 3.2v for .5a)

But… Regardless , it seems 3.6v on the side switch and 2a on the led indicator, right?


Did you read the review? You need to go do that.