Battery charger light nearly always green

[pvogel]

I bought a second charger for the house (while having another at the office) as well as a bunch of spare batteries in prep for a multi-day ride coming up and that has led to a couple of questions:

1. When I put the iphone into the phone booth with a spare battery and close the door, the iphone immediately goes into the "charging" display -- that's what I would expect if the spare battery is used to keep the iphone "topped up" on charge while I ride, so I'm draining the spare battery from the minute I start. That's totally fine, and what I expect, but after I ride a while, it seems the iphone is draining its own battery and I don't see the charging indicator on the iphone anymore -- what happened?

2. After a commute (13 miles, ~40-50 minutes depending on weather and traffic lights) the iPhone is down to about 50% or less charge. More often than not, putting the spare battery into the charger, the light never moves away from green, suggesting the spare battery is fully charged. Is that correct? It doesn't seem in keeping with the idea that the spare is supplying a gentle charge to the iphone throughout the ride, or the lipo charger here is way too tolerant of minor discharge.

3. At the office, I do, occasionally, get a red (presumably indicating "charging") light on the charger for a while -- I've *never* seen the red light at home, even with a battery fresh out of the shipping package and never charged -- are you shipping these things fully charged? I thought proper storage charge for a lithium battery is to 60-80% of capacity, which should mean a newly shipped battery needs a ~20 minute charge to get there. Is it possible my second charger is faulty?

4. The batteries don't have a real positive "snap" into the charger (or the phone booth) and I've seen a couple of times that I had to wiggle the battery to get the charging indicator to light -- is this expected?

Peter+

[pvogel]

OK. I've figured this one out with the help of my multimeter and my RC-related Lithium Polymer battery chargers...

On the second charger I ordered, where the light has *never* not been green, even with a battery I knew to be basically fully discharged (the iphone was charged from it during half my ride, and then discharged down to 20%, so the phone booth secondary battery was unable to continue to charge the iPhone, and putting that battery in the charger at work I immediately got the red charging light) I did some tests with the multimeter:

1. the pins that contact the battery deliver *no* voltage, reading in the 10ths of millivolts, which is pretty much what you get when you hold the probes in your hands and squeeze... Since these are single-cell LiPo batteries, the charge voltage should be on the order of 4.2v and the capacity of the battery is 1050mAh, so the charge current should be about 1Amp or less.

2. Sliding the battery carriage off the charger to get access to the connecting pins, the multimeter reads, yep, 4.2 volts at those pins.

3. Speculating that I wasn't getting a good connection between the charger pins and the battery carriage, I bent the pins up a little further and tried again. Still no joy

I conclude that this charger is defective, either the pins on the charger aren't making contact with the carriage backplate or there is a discontinuity within the carriage between the battery contact pins and the backplate pin contacts.

I still want a second charger for home, John, how do you want to handle the return/replacement/whatever?...

Peter+