Corroded Eneloop Pro AAA's? Rough Blue Tops

Hi guys,

I signed up hoping someone might be able to help me.

I bought two packs of Eneloop Pro AAA's. I opened one pack six months ago and I just opened the second. The pack I just opened has a sandpaper like feel to the top of the batteries and is coloured blue. The pack I opened earlier has smooth black tops.

The 4 blue tops are stamped June 2015. The 4 black tops are stamped June 2016. I bought them together.

I was wondering if there's something wrong with the blue ones. Corrosion etc?

Thanks for looking.

Hi Aurora Jackalis,

there is nothing wrong with the 4 blue ones.

- I can see the blue ones are BK-4HCCE - 4th generation Panasonic Eneloop Pro AAA, 500 cycles, min 900mAh
- the black ones are most likely BK-4HCDE - 5th generation Panasonic Eneloop Pro AAA, 500 cycles, min 930mAh

Reference: http://eneloop101.com/batteries/complete-lineup/

You bought them together, but you bought different generations of the same thing. Don't worry, both will serve you well

Cheers,
AA Cycler

I'd just take care of not mixing cells of both batches in one set that gets used together because, as you noticed, the two generations of cells have slightly different capacity. Also even if they have the same cycle rating, newer cells tend to have a better cycle life (maybe also because they haven't been sitting around for that long). So if you use the batteries together, the older ones will probably fail first because they already start with a slightly lower capacity, and this will get worse over time since they are always discharged deeper than the other ones.

Here's an example for two comparable cells from diffrerent batches. As you can see, the newer ones last about 15% longer than the older ones, and this might as well happen to your cells.
(These are AA cells, but I just realized no AAA Eneloop Pro or equivalent cells have been tested yet)

http://www.aacycler.com/battery/aa/panasonic-eneloop-pro/

AA Cycler said:

there is nothing wrong with the 4 blue ones.

Click to expand...

Great!

Kurt_Woloch said:

I'd just take care of not mixing cells of both batches in one set

Click to expand...

Good tip. I'll do that. It looks like I should keep track of how much all my rechargeable have been used.

Interesting links too. Thanks for for taking the time to help me.

They both have the 4th Generation model # BK-4HCCE.

Have you tested the batteries by discharge? If that is possible, please let me know.

Hi,

I'm new to rechargeables. These were half price from Bing Lee (which is a prominent Australian retail outlet) so I bought them before I needed them during the new year. I only just got my charger this week - A Nitecore D4. Do you want me to discharge them in the Nitecore or in a device?

Both? Dont know if that charger can measure capacity while discharging?
I assume you dont have the packages anymore?

I don't have any high drain devices. I've started down the rechargable route for long term savings.

My limited research suggested it was a good charger. I haven't used it yet.

I kept the the packaging of the blue tops when I noticed they were different to the others. I can take photos over the weekend.

Great. Take some pictures feom front and back. Especially some close up of the front, thanks.

You could test them in any device for rough measurements.

Here you go.

The back has the chain's sticker obstructing the details.

And when I try to remove the sticker it's ripping the back of the card off.

Thanks for the pics. I double checked my own Pro and they are blue tops as well. So blue tops are fine.