Poll - What Voltage Does Your Pila Charge to?

I've been curious about this for some time. I don't mean to imply any value is better than another nor that Pila isn't a great charger with a safe algorithm.

Wow, a charger that charges over 4.2??? :duck: Thats a waiting to happen.

I use the cheapo $6 DX 18650/16340 with absolutely no problems, and it charges to exactly 4.20 volts each time.

I didn't vote, as I don't own a Pila, but.....

SmurfTacular said:

Wow, a charger that charges over 4.2??? :duck: Thats a waiting to happen.

Click to expand...

The charging specification for the termination of charge for lithium cobalt cells is 4.20 Volts +/- 0.05 Volt, or 4.15-4.25 Volts. Most problems/dangers with LiCo cells don't occur untill >4.35 Volts, although the higher the termination voltage, the more oxidation that occurs, which degrades the cell.

Dave

SmurfTacular said:

Wow, a charger that charges over 4.2??? :duck: Thats a waiting to happen.

I use the cheapo $6 DX 18650/16340 with absolutely no problems, and it charges to exactly 4.20 volts each time.

Click to expand...

Not one vote over 4.2 What are you talking about?

I wish we got more votes. Either not many Pila owners or folks don't like to share. I'm disappointed.

Well, from this data it looks like I would have a 50:50 chance of getting a Pila that charges to something closer to 4.2 if I return mine. Nobody's charger charges LOWER than mine (4.16) so it looks like I have nothing to lose if I can get the dealer to exchange it. Of course since he and Pila both say it is within spec the dealer may refuse.

As far as me being overly concerned with final charge voltage I wonder how many owners whose Pila charges to 4.2 would like to trade for mine that charges to 4.16?

I've been using a Pila charger for about a year. After the light turns green I always check the battery voltage. It's typically 4.17 volts. If I put the battery back in the charger or push the reset button charging will resume. On my RCR-123s it takes about thirty minutes for the red charging light to turn off and the green light to come on. The battery has always tested 4.197 volts after the top off. Thats good enough for me and I remove the battery. I didn't vote because my Pila dependably gives me two options.

Well its hard for me to answer this question. First of all my DMM is a cheap on, so it may not be accurate. Sometimes the end voltage varies very slightly depending on the battery I charge. There is a difference between the different charging bays as well...

For what its worth:
14500 - charges to 4.19-4.20 (channel one) 4.20-4.21V (channel two)
18650 - charges to 4.20 (channel one) 4.22V (channel two)

These are fairly new batteries.

maskman said:

I've been using a Pila charger for about a year. After the light turns green I always check the battery voltage. It's typically 4.17 volts. If I put the battery back in the charger or push the reset button charging will resume. On my RCR-123s it takes about thirty minutes for the red charging light to turn off and the green light to come on. The battery has always tested 4.197 volts after the top off. Thats good enough for me and I remove the battery. I didn't vote because my Pila dependably gives me two options.

Click to expand...

That's great. When I hit reset or take batteries out then put them back I may get a red light from 1 to 10 minutes but voltage of batteries remains the same. My dealer kindly agreed to give me a new Pila so I can't wait to see how it works. Yours gives you a choice. That's neat.

recDNA said:

That's great. When I hit reset or take batteries out then put them back I may get a red light from 1 to 10 minutes but voltage of batteries remains the same. My dealer kindly agreed to give me a new Pila so I can't wait to see how it works. Yours gives you a choice. That's neat.

Click to expand...

My new Pila seems to do the same thing. Do I need to try and return it also?
I get anywhere from 4.13 to 4.16 it would seem.

loquutis79 said:

I get anywhere from 4.13 to 4.16 it would seem.

Click to expand...

Cheap nimh chargers terminate based on time (push power for 60 minutes than stop)

Cheap lithium ion charge terminate based on voltage (push x volts in until y volts comes out)

The whole reason to pay extra for a Pila is that every cycle is tailored to the what the cell needs/wants. It stops when the cell is ready. Think of 4.20v not as full but as the max safe limit. 4.12-4.18v means your cells will last longer.

My Pila terminates consistently at 4.19v or 4.20v.

If your Pila is terminating as low as 4.13v, it's a cause for concern.

Either your cells are coming to the end of their cycle life, are damaged and not able to take a full charge, or there is a fault with your Pila.

Try some different cells in your Pila to rule out a problem with the Pila.

Maybe there is some confusion here.

When asking "what does your Pila charge batteries too" as the name of this poll asks, I figure that means the battery resting voltage off of the Pila at the green light.

My four brand new AW18650 1300's are reading between 4.13 to 4.16 which many have told me this is a good thing [more cycles as in post #10 by ElectronGuru. [Thanks for that]

Trancersteve, are you talking about what the Pila unit itself TERMINATES its charge at while charging the batteries? If so, I have not measured that yet but I am hoping that it will be 4.2 max. WHILE charging. I will test that when I get a chance and report back.

I just want to make sure I am understanding all of this.

Thanks all.

So far mine has terminated at 4.18 every time.

diesel79 said:

So far mine has terminated at 4.18 every time.

Click to expand...

Nice. But I am still confused Diesel79. Are we polling the chargers termination voltage WHILE charging, or the voltage of the battery which the Pila charges it to. There is a big, important difference here.

Poll asks "What voltage does your Pila charge new batteries to?"

This could and should be slightly lower than the 4.2 termination voltage I understand. That is, if I understand? :]

The Pila charger does not terminate at any specific voltage, it terminates when the current has dropped to a specific value.

What charge voltage the charger uses, must be measuring while it is charging and cannot be measured when it has terminated.

On the chart below a typically charge sequence can be seen (This is not from a Pila, but is CC/CV).
The CC part is where the current is constant and the voltage is rising, when the voltage reach the charge voltage, the CV phase is started. The voltage is constant and the current will drop, until it reaches the terminating current (0.1A in the chart). When the charging current is turned off the voltage will immediately drop a bit and then drop some more over time. How much the voltage drops depends on a lot of factors.

According to most LiIon specifications the CV voltage must be between 4.15 and 4.25 volt. In my DMM guide I explain how to measure this voltage (Charge voltage chapter).

loquutis79 said:

Nice. But I am still confused Diesel79. Are we polling the chargers termination voltage WHILE charging, or the voltage of the battery which the Pila charges it to. There is a big, important difference here.

Poll asks "What voltage does your Pila charge new batteries to?"

This could and should be slightly lower than the 4.2 termination voltage I understand. That is, if I understand? :]

Click to expand...

Sorry about that, I wasnt very clear. Mine has charged my brand new Redilast 18650 3100mah to 4.18 every time. In fact Ive got 3 brand new ones in the mail yesterday, 2 of which are currently being charged. When they are done I will post what they read right off the charger.

Well so far I have been only topping up these very new cells.
I will run them down a fair bit this time and try again. I would like to see 4.17 or so. But then again maybe I am over thinking this.

With my new round if batteries it charged 2 of them to 4.13 and one to 4.15. All of my others it has charged to 4.18 everytime. I'll run them through a few cycles and see if anything changes.

Old thread but still a good topic since the Pila is often recommended on the forum. I have always wondered if I had a dud Pila or not. I used to charge 14500's, 18650's, and 26650's (with a jumper contraption) with the Pila and all of these cells when they were finished charging come out of the cradle at 4.13 every time.

When my interest first started in all this I wasn't sure if it was my DMM or my cells, or the charger. Since that time I have gotten other chargers and used many brands of cells and gotten a second meter. Both my meters read exactly the same so I feel more confident that is not an issue. I have also found that my preferred way to charge li-ion cells is with the smart chargers from battery space. I have 2 of them that charges at 1.8 amps and they terminate perfectly at 4.20 v and charges faster too.

I still use the Pila sometimes but the smart chargers are good quality and compact and seem to do a better job of getting juice into the my cells.

Please don't say "terminate at X", when you mean "measured X right after the charger stopped". It's not the same thing.

I agree Shadowjk, there is ALOT of confusion on this point. In general people seem to mix the two up.
I am sure my Pila terminates at 4.2, however I still wonder why so many say they get 4.18V at rest consistently off the charger and my new AW18650's are always 4.13 or 4.15.