I have a large inventory of AA Eneloops of varying age and the Powerex 8 cell “smart” charger. In preparation for a liveaboard trip this weekend I set out to charge them since I’ve not been in the water for a month. Something has gone wrong as the batteries never complete the charge cycle, whether a normal fast charge, a soft charge, or a reconditioning cycle. I’m guessing it’s the charger, since this is happening regardless of the age of the batteries. Does anyone know how to test the charger, or if this is a known issue with (hopefully!) a known remedy? I am in Fiji and can only find super cheap 2-cell chargers which would not be ideal, I’m out of time to order a replacement, and I would hate to have to buy and pack 96 alkaline batteries at $4 a pop!

I have found that sometimes the battery end contacts form an oxide layer that increases resistance. Spinning them in the charger will help them to make better contact and complete a cycle.

Good advice in general, for sure. But not the cause of my current (!) problem.

It sounds like lights come on the charger but it doesn't charge, is that correct? I assume you have tried unplugging the charger and plugging it back in. Try unplugging the barrel jack to the charging cradle and clean that too. Try charging only a 2 or 4 batteries at a time and if that doesn't work, swap them to different slots.

Have you used this charger in Fiji before? The back of the charger will be stamped with the charger input AC requirements. It should say something like 100–240 V AC, 50/60 Hz. This is most likely not the problem but worth checking. According to the internet the outlets in Fiji are 240 V/50 Hz so if the charger is only for 120V/60Hz, that would be an issue.

Edited 2 hours ago2 hr by brightnight

Thanks for the ideas. I have checked all of those things and yes I’ve been using this charger here for a year without issue.

Since my first post, I’ve now had two batches of cells complete the full charging cycle and one batch not complete. I checked voltages to confirm. It’s clear that the charger is working only intermittently.

I did manage to find a cheap 4-cell charger that is very slow. (And just by the way, the only replacement rechargeable Energizer AAs here are USD 8 per cell!). I will just have to limp along and hope for the best on this trip.

So much for the conventional wisdom that AA batteries are superior to LiOn because you can buy them anywhere...

For what it worth, i used a pair of 4XAA chargers that are USB-C PD powered. Redundancy and no issues with local power supply. Carry a 60W USB brick and run all chargers off of that

I have been using 8-cell Power-X chargers for many years. My 4th copy is black whereas the 3 older are grey. I am looking at the tiny label on the bottom of the black one now - It has MH-C801D in the name but no mention of smart. Mine all came with AC adapters for US current that connect with a DIN type plug. The only issue I have had is that segments of the LCD display seem to fail after a while (years). This happened to one unit of my first two bought (close to 2 decades ago) so bought #3 and more recently #4. The now 2 units with a semi-functional LCD still charge but hard to tell with missing segments. It is a good idea to have 2 of any type of charger so one can swap them out or have two to charge more batts (16 at a time is minimal for Retras).

A possible issue on boats is unreliable electricity. This was a problem on a research vessel I have been on. So all computers were plugged into UPS units. On one cruise it was reported that one UPS unit caught fire as a result of the ship's poor power (a 1960s vintage vessel) on the previous cruise. I would not be surprised if the longevity of power adapters is much less when used on boats. Possibly with portable generators as well.

Edited 8 minutes ago8 min by Tom Kline