Pila IBC Charger Issues??

Batteries and Chargers Chargers
1

I just got my new Pila IBC charger in the mail on Saturday. I have run two sets of batteries through it so far and I'm concerned with the output voltage. Keep in mind I'm a noob to this class of lights and batteries. I was under the impression it was suppose to charge the batteries to 4.2 volts. The first set of batteries was a pair of Callies's Kustom 3100mAh protected 18650's. The second set was a set that came with my new Ultrafire WF-502B. It is a pair of Ultrafire 3000mAh unprotected 18650's.

The first round of charging on both sets gave me 4.14 volts measured with my Fluke meter. I used one of the CK's yesterday while working on my truck and re-charged it last night. The net result was 4.12 volts.

Is something wrong with my charger?

I don't currently have any other batteries to run through it at the moment. I have a bunch of Trustfire 3000mAh batteries on order but it will likely be a month before they show up on my doorstep.

2

Voltage will vary to some degree with the condition of the battery itself. Generally, the older the cell, and/or the higher the internal resistance, the lower the voltage will be once taken off the charger and given time to cool down and 'rest'. More often than not, older cells will have higher internal resistance than a newer cell of the same type that has been treated in the same way, but different types of cell can have different IR values to begin with.

Even with fresh, quality cells, your battery is going to have a different voltage while charging than when at rest, and some difference between the two states normal.

When putting current in to the battery to charge it, the temperature will rise. That change in temperature will change the resistance, and as V=IR, if we assume that the current is a constant, as resistance changes, so will the voltage.

Likewise, when charging ceases, the temperature will drop, resistance will be reduced, and the voltage will decrease.

So, your charger reaches 4.20v, but that is under load. With the load taken off, the voltage drops. Cells that are charging and cells that are at rest are subject to two different sets of conditions, and the voltage readings vary accordingly.

I cannot promise that your charger is working perfectly, but I can say that it is entirely normal and expected for the cell to have a voltage lower than 4.20v once taken off the charger and given time to rest. The older cells, or those that have higher internal resistance for whatever other reason, will tend to have a lower voltage after resting than newer, better conditioned cells.

3

I say it's better to be slightly under charged than slightly over charged. That said, both my Xtar WP-2's charge about the same as your Pila. I wouldn't worry about it..

4

Hello:

That's pretty close to the voltages I get with various cells coming of the Pila. No worries!

Dave

5

Ordered a Pila charger 3 days ago. Found a good deal on one finally. Been looking at it for 6 months and finally made the move now that they are again available.
I am currently using an excellent Intellacharger NiteCore charger but it charges at a constant rate. It takes considerable time to recharge one or up to 4 18650’s.

I read some reviews of the Pila and it charges more rapidly initially to speed up the process and then tapers off the charge. I have a smart automotive charger that does that and it works exceedingly well. I will post charging results when I receive it in a few days.

6

Pila IBC is the one and only charger I have and I love it,had a few cheapies and they are in the trash because of problems.Pila will give you trouble free service for a long time,IMO worth the extra $$.(p.s. nice old thread revival)