LiIon batteries
10-03-2018, 04:55 AM
#3
No particular voltage. Most will do 2 or 3 flights on a full charge then track how much it takes to bump them up to a full charge. Do this a few times and you can get a fairly accurate estimate of how much current is consumed per flight. This will give you a good idea of how many flights are safe on a charge.
10-10-2018, 04:49 PM
#8
I fully charge and fly a 10 minute flight . Recharge to track mA put back in after the 10 minute flight and this gives you the actual mA's used per 10 minute flight . This way I can figure how many 10 minute flights I can get in before reaching the 50% use of pack capacity mark I set before recharging again . 50% gives you a wide safety margin
10-10-2018, 05:33 PM
#9
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Sorry
i guess I’m not making myself clear....at what voltage of the pack do you recharge. I’ve been using 7.1 volts under 1 amp load I recharge. But then if you’re at 7.4 volts before first flight do you go ahead and charge?
This is a curiosity thing just wondered what you all are doing
This is a curiosity thing just wondered what you all are doing
10-10-2018, 06:06 PM
#10
I thought you were quite clear. Perhaps it is us that are not being clear. Charging any lithium based batteries based on voltage is a bad idea! The voltage drop off as the battery reaches the end of its capacity is very steep and it is not a good indicator of how much capacity it left. To know how much capacity is left you need to figure how much is being used. That is why a few of us suggested you do a couple flights on a fully charged battery and take note of how many ma it takes to top off the battery. That information can be used to determine how many safe flights you can do between charges.
10-10-2018, 06:20 PM
#11
Using your method I would stay with the 7.1v cut off point and definetly go no lower than 7.0v before recharging. I would also always top off before the first flight of the day regardless of voltage drop if using your method . If using the method in my previous post I would have more confidence of the residual capacity in the pack . Reading a voltage drop in my opinion isn't as informative as knowing the calculated mA capacity remaining based on previous useage data .
10-14-2018, 04:32 AM
#12
I know very little about battery chemistries but the above recommendations work for me. My larger planes use two 5200 mah Fromeco batteries (plus ignition on some) and I burn 300 mah or so per battery per flight. Or so the charger says after refilling the batteries.
