Funkawa Shockli AA Size Lithium Iron Phosphate 650mAh Rechargeable Battery

aprwx: I'm completely re-writing my review. I had previously given a 1 star review saying that the capacity wasn't a fraction of what they claimed.

After some thought, I realized that they perhaps didn't ship the batteries with a full charge. I believe this is the case, and then putting them in solar lights 'dead' in a Minnesota winter gave it no chance to charge up the batteries to capacity.

To test this theory, I bought a special charger that does 3.2v batteries. It also allows you to test the capacity. As expected, the batteries were dead, but after charging and running a test -- showed that they had 608 mAh capacity (one battery test), which I think is acceptable (they are never right on with the specs, and still far better than the 300 mAh batteries that came with my solar lights).

I put them in the solar lights and they were bright all night long. Any issues I have beyond this point is going to be on the solar lights, and not the battery since their capacities are good and holding a charge.

So the only recommendation I have for people is to get a 3.2v charger and charge them up when you get them, as they may be shipped dead. [this is typical of some...

United States on Nov 30, 2023

Joe: Just replaced 2 string lights this week with these batteries. Light are as bright as the day I put them up. These batteries may outlast the solar panel.

United States on Oct 30, 2023

GaryD: I purchased the Shockli 4 pack in July, but first needed them in October. I charged two batteries separately, using an IMAX B6 Mini charger in the LiFePO4 mode. They needed only about 60 mah to bring them to full charge. I then used the batteries in series to power an ESP32 module. When the power was depleted below operating level, I measured the voltage as just above 2.5V on each cell. I charged each battery using a 0.2 Amp charge which should be roughly a 0.3C rate, This rate is within the range of acceptable charge rate for LiFe batteries. The maximum capacity was approximately 490 mah in each cell, The full capacity voltage was as expected. A second cycle of both batteries yielded the same capacity. This is quite a bit lower than the expected 650 mah stated on the cells.
Update 10/10/.2023
Without prompting on my part, Shockli offered a refund for the batteries. I had not anticipated that level of standing behind their product. I have changed my overall rating to reflect my view.

United States on Oct 06, 2023

Nathan Smith: As far as I can measure, the batteries have the capacity they claim (if not a tad more). None of them have obvious shunts or other problems. It's a low bar to clear, but it's one a lot of other products unfortunately don't.

United States on Feb 20, 2023

CJ C works in I.T.: Bought these to use in a "4xAA" battery case for an amateur radio handheld transceiver to increase the voltage from the AA 6 volts nominal to the LiFePO4 12.8 volts nominal, allowing for a doubling of transmit power over AAs on the particular radio being used. Granted, the 650 mAh is not much at all for a high drain device, but this would be sufficient for short transmissions and conversations. Unfortunately, the radio was left on accidentally to the point it started cutting off, so I popped the battery pack out and placed the cells on the charger. I found that one of the four would no longer even accept a charge. I don't know how a solar light (for which these are advertised) would *not* discharge fully overnight during use, but if they do run until the battery is dead, they'll cause similar damage.
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I do realize these are not marketed for ham radio use, and I'm not an idiot, I do know the low mAh rating wouldn't be much. I was, however, more concerned with voltage than capacity; I could have easily bought Lithium ion cells, but with the 4.2 volts they have when fully charged, I would need to use only three cells with a dummy fourth cell to keep voltage below 15...

United States on Jun 08, 2021