Luna Charger issues

[Tom3holer]

Hi,
Just received my first ebike. After researching what was available I chose F6 Euybike as my first e-Bike.
I have a degree in EE so have read a plethora of articles on the care and handling of E-bike batteries and feel well informed wanting to give the the best treatment.
I bought an extra battery of the same size both electrically and physical. The bike and batteries are in a detached garage.
The Luna Charger seemed to be just the thing to be able to control charging current and charge percentage. The only problem is it does not do percent of charge other than 100.
The first time I used it; set at 1A and 80%. I kept an eye on it off and on and the last time I went in it the voltage was 54.5 and it was cycling on then off every 2-3 seconds. A relay clicking and the fan coming on then off. I sent an email to Luna and their response was "As mentioned in the manual the charger works best with our batteries only." WTF!

I did read this in a couple of posts during my research but the were 3-4 years old and figured they must have fixed that by now.

So how does one calculate the time needed to charge a known battery votage to 80% of its full rating?

Thank you,
Tom

 

[major masingil]

I did it through trial and error. You can set up a table based on your battery's 100% charge voltage. Use your battery down to 40% to 50%, then start charging and take voltage measurements periodically. The time depends on state of charge of the battery. Its not exact but gets you pretty close. After some experience you will have a good idea on how long to charge based on state of discharge. I ended up going with a timer which I plug into the outlet and set it for the desired time for the desired state of charge. When the timer expires the power is cut to the charger

 

[major masingil]

BN-LINK 12 Hour Indoor Mechanical... https://www.amazon.com/dp/B00MVDTEXS?ref=ppx_pop_mob_ap_share

 

[Tom3holer]

Interestingly That test was done on the factory battery for my F6 Euybike.
I purchased a second battery after the bike arrived as there are a few 45-50 mile rt trail rides I wanted to try.
The battery was slightly bigger and was 1.5lbs heavier. After depleting it down to 47v I put it on the Luna and to my amazement it charged it to 51.3V or exactly 80% and stopped with the green light on. Wil have to investigate this a bit more but am keeping it for now.