LiitoKala Lii-500 Charger - NOR test hangs a long time after fully recharging

mickyd

10 W
Joined
Sep 12, 2022
Messages
73
Location
Sunny San Diego
When doing the NOR capacity test on my new Lii-500 charger, once the discharge cycle is completed, the NOR indicator flashes the word 'END' . When the batteries come up to FULL charge, the individual cells NOR indictor continues to flash END for 1/2 to 3/4 hrs. before eventually going SOLID.

Since it takes so long for the indicator to stop flashing once batteries come up to full charge, and I'm wondering what the heck the unit is doing???? It's bad enough that the complete test takes over 8 hours, but then to wait so long for the indicator to stop flashing before taking the batteries out is taking me over the edge. Today, I pulled the batteries as soon as the tester showed full voltage in order to get another test going.

So, if anyone else has the same unit, are you seeing the same thing?? If anyone knows of a good reason for lag happening, please share it. It's making me want to return my unit if its not acting right.
 
I think I now understand why the charger appeared to 'hang' when the cell reached its full 4.2V charge. It was NOT actually hanging, but instead, the cells VOLTAGE was remaining constant while the cells CAPACITY was still slowly increasing, which I hadn't noticed on the display. I was just focusing on the voltage thinking the charge should be completed.

I found a website that showed this graphically. The author included quite a few graphs that showed various charging cycles over time. The graphs plotted CURRENT, VOLTAGE, and CAPACITY.

I attached the graph that caught my eye. Toward the end of the test at about 180 minutes, you'll notice the VOLTAGE remains constant for another 40 minutes, while the the cells CAPACITY continues to rise. Also notice during this time, the CAPACITY slowly drops off until 225 minutes, at which time the recharge was complete, and the display indicator 'END' would go from flashing to solid.

Lesson learned......much to learn. Don't pull the cells off until the END indicator goes solid. :D

Oh, the website was http://lygte-info.dk/review/Review%20Charger%20LiitoKala%20Lii-500%20UK.html The author did a really nice review of the LiitoKala.
 

Attachments

  • chrome_TUNothfxfi.png
    chrome_TUNothfxfi.png
    189.3 KB · Views: 356
I started a thread in the GENERAL DISCUSSION section but probably should have posted it here. Didn't know if I could switch it.

Here it is: https://endless-sphere.com/forums/viewtopic.php?f=1&t=117846
 
This graph shows what is described as an 'older cell', reaching full charge 4.2V after 75 minutes, but not reaching full capacity until 250 minutes!!
 

Attachments

  • Screenshot 2022-10-02 170602.jpg
    Screenshot 2022-10-02 170602.jpg
    152.9 KB · Views: 352
There's a lot that you can unpack here, if you want to go down the rabbit hole of battery chemistry and all the fine details about processing and testing. But let me ask this: you know that the END icon starts flashing once discharge has finished, you have the measured discharge capacity and can record it on your cell. Now it's just charging it all the way back up to full during that flashing period. . Do you need it at full? Storing cells at 100% capacity isn't great for their longevity. I pull mine (18650's, that is) out of the charger when I see that they're at about 3.7-3.8v, because I know that to be a good storage charge for long periods of time. I perform a separate balance prior to building a pack.

If you're going straight into building your pack after you pull them from the charger, then by all means let it finish its thing, its top balancing if you do it that way.
 
harrisonpatm said:
There's a lot that you can unpack here, if you want to go down the rabbit hole of battery chemistry and all the fine details about processing and testing. But let me ask this: you know that the END icon starts flashing once discharge has finished, you have the measured discharge capacity and can record it on your cell. Now it's just charging it all the way back up to full during that flashing period. . Do you need it at full? Storing cells at 100% capacity isn't great for their longevity. I pull mine (18650's, that is) out of the charger when I see that they're at about 3.7-3.8v, because I know that to be a good storage charge for long periods of time. I perform a separate balance prior to building a pack.

If you're going straight into building your pack after you pull them from the charger, then by all means let it finish its thing, its top balancing if you do it that way.
Just noticed your post today. Never got a push notification. Sorry there was so much to unpack. I wanted to cover a lot of bases....hopefully not confusing.

I'm aware its not recommended to store batteries at full capacity. The only reason I was allowing the LiitoKala to complete its cycle was because I was interested in running the test twice just to see repeatability and to also just get an understanding of the complete charge cycle. Appreciate your feedback.
 
Back
Top