Experience with paleblue batteries?

Equipment
1

Hi,

has anybody tried to use paleblue rechargeable AA batteries in the battery compartment of a FT-817?
https://paleblueearth.com/products/pale-blue-lithium-rechargeable-aa-batteries?variant=39957854781595

They claim to have a capacity of approx. 1500 mAh / 2.24 Wh, but I couldn’t find any information about the discharge curve and high current behaviour at various temperatures anywhere. I’d be interested in a comparison with standard AA NiMh cells in practical experience. Although I could get them discounted at the moment, it’s quite an investment for try and error.

73 Jens HB9EKO

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2

Can’t contribute that much to these specific cells, but the sure shot would be white Eneloops. I wouldn’t try any other NiMH cells.

Ahoi
Pom

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3

I had a private discussion with someone who tried some of these AA with a built in charger cells and he wasn’t impressed. I just can’t remember who it was right now. I need to check on my shack PC not work PC.

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4

Fully agree concerning the Eneloops. By the way: IKEA Ladda are re-labelled Eneloops as well.

5

For the 2 Ampere current draw the black Eneloop Pro make sense.
There you have about 2500 mAh

But I think the way those pale blue cells are designed make no sense for the 817. Or do you want to connect 8 microUSB leads to charge every cell at the same time ?

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6

I have a number of these AA Ladda and have found them to be excellent. Mine are the older white ones, they are now blue. I’ve been charging them with IKEA’s own 2 cell USB based charger, takes a while due to limited charge current but it does mean you are less likely to cook the cells.

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7

TLDR: black eneloops give an actual 2400mAH (tested) to the radio, and will charge in the radio.

So to answer your question, I think they would be crap!

Either

a) they have a switchmode regulator in each battery → all you will hear is noise

b) they have a linear regulator → half the energy is lost.

c) whatever regulator, it might not deliver the 2+ amps the TX needs

d) A generic 14500 lithium (full length AA) is rated 800mAh. These are short 1/2 or 2/3 AA cells inside (at best) .

I am not believing the 1500mAh rating, even with a switchmode.

So maybe 1200mAh with a switchmode (but unusable for RX) or 500mAh with a linear regulator.
Or less

I tested my eneloop pro (black) at 2500mAh and some Aliexpress NIMH at 1850mAh

https://groups.io/g/ft817/message/112405

I am trying some NCR18650GA’s right now, rated at 3400mAh according to the test labels on them, but I am getting less than 2000mAh on the tester, not sure why.
So far I havn’t found lithium rechargeables with better tested capacity than black eneloops.

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8

Eneloop pro absolutely make sense, if you’re looking for batteries with a high self-discharge and a small number of duty cycles.

9

I got good performance in my old 817nd using Amazon NiMH AAs in the factory tray. I got enough run time to comfortably activate a summit (always carried a spare set). NiMHs, at least the Amazon ones, are slightly “fatter” than regular AAs and would fit tightly in the tray. To mitigate this, I removed the center divider in the AA tray. I also loaded/unloaded the tray with it in the radio to avoid scraping the battery insulation as I inserted or removed the tray (mainly an issue while removing it loaded).

Chris

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10

That wouldn’t be the issue. I use internal batteries only for single activations of max. an hour or so. My Eneloop (Ikea Ladda) batteries for this purpose start to show the first signs of age after more than 2 years, so sooner or later I need to replace them anyway. I was wondering if the Paleblue batteries with rated 1.5V would make sense in this context, since I just saw them on a sale. But there are other reasonable arguments against using them.

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11

Fully agree with the Ladda, I also got the white ones. This winter, I realised that they start showing the first signs of age at low temperatures: In the beginning, I had to switch the FT-817’s power from 2.5W to 5W in the beginning, then the output would fall back to 2.5W after an hour or so. Now, the power falls back to 2.5W after 10-15 minutes. It seems like the internal resistance increases with lower temperatures causing the voltage to drop further when transmitting. Maybe this gets better again in spring, but anyway, they are a great value for money.

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12

I have tried various types of rechargeables since 2001 when I bought my FT-817. (Anyone still remember NiCd cells? :slight_smile: ) I still can’t make a valid statement concerning operating time vs. rated capacity, not even with cells from different manufacturers and same chemistry. That’s why I was asking if anybody had practical experience with these Paleblue cells. Assuming a constant voltage until they are flat could have some advantages (theoretically). But as you mentioned, there are so many ifs and maybes involved that I’m reluctant to spend 3 times the price of other batteries to go experimental.

13

817 with no internal batteries and Anderson connector adapter fitted. LiPo with Anderson connectors. 3m cable with Anderson connectors each end.

817 in hand, LiPo skulking in my bag or jacket pocket (warm). Activation underway.

LiPo seems to last & last, making the extra weight worthwhile.

Wouldn’t bother with internal batteries.

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14

There’s not going to be much experimental about it. But I’d like to see you buy one, test it, and then open it up. I couldn’t see a teardown or anyone who actually measured them online.

They are pretty certain to be a switchmode regulator inside. ( so not going to work for the RX)

They can’t contain much battery material -there is only space for 2/3AA at best.
However they say it’s lipo, so probably a really tiny little rectangular lipo fitted inside, and even less capacity.

So lets be optimistic and run with
2/3AA * AA@800mAh = 533mAh*3.7V *90% switchmode = 1.78Wh, ~ 1200mAh
Black Eneloop 2500mAh * 1.2V = 3Wh

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15

I found the comments, they were from Martyn @M1MAJ who tried some alleged 2400mAh cells and found they were only about 1600-1880mAh at best. He wasn’t very impressed.

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16

Sorry, I would if I had use for 8 AA batteries for something else, but everything I could use them for shouts for triggering some sort of current or overheating protection. So I’ll rather join you in wanting someone else to buy and test them.

If the same real-to-claimed capacity ratio applies to those cells, then the best risk management strategy is to stick with LADDA cells and invest the difference in some other Swedish goodies that end up in the shopping basket when I go there with my wife and my daughter :slight_smile:

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17

Today, I stepped over a Youtube video that anwers our questions: https://www.youtube.com/watch?v=1wtYVqaxRhE

I don’t own a KX1, but the manual which I found on Elecraft’s website says that it uses 300-700 mA in TX. If these batteries last only 19 minutes, then never mind with a FT-817…

73 Jens

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18

I have an update concerning those USB 1.5V batteries:

A couple of months ago, I saw a set of 8 batteries on a chinese online platform for a price that matched my curiosity. (Approximately the price of 8 AA cells from the Swedish furniture store). So I decided to give it a try, mentally putting them to use in remote controls etc. in case of uselessness.

They are labelled “AOAE”, have a USB C charging port and claim to have a capacity of 2700 mWh, which corresponds to 1800 mAh@1.5V. A bit higher than the Paleblue batteries, but not very far from plausible values.

When they arrived, I first put them into the FT-817 and noticed no audible difference in noise compared to a connected external power supply.

Equipped with a spare battery, I gave them a try at an activation today and was positively surprised: With the FT-817 set to 5W output power, I managed to get 1h15min continuous operation time in CW. (i.e. either having QSOs or calling CQ). When the batteries were depleted (during a CQ call), the TRX switched off, then after a second on again, and the display showed 9.5V.

Temperature at the car park was -1°C, at the summit probably a degree or so lower. There was no voltage drop during the whole activation. The temperature probably supported that there was no overheating which would trigger some kind of protection.

I don’t consider that bad. For comparison: NiMH batteries in the battery compartment give me an operation time of roughly 1 1/2 hours, but after a while (depending on temperature and age of the batteries), the output power falls back to 2.5W during operation, so I constantly have to have an eye on this.

All in all, for short activations, these USB batteries seem to be the better option for me, since they keep their output voltage constant until they are depleted. When I plan longer or several activations, I’ll carry an external battery with me anyway.

Yet to be tested: operation time with 2.5W output power, and activations in hot weather to see if this triggers any temperature protection.

73 Jens HB9EKO

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