Quote:
Originally Posted by redpoint5
Results are in.
My "40v" batteries measured 40.64v fresh off the charger.
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Makes sense considering
Quote:
Originally Posted by redpoint5
I've used the batteries for 1.5 years to mow the lawn, blower, and chainsaw during the ice storm. I consider the use to be normal.
An hour discharge is pretty unusual, as the mower would deplete the battery in probably an hour or less, the chainsaw in probably 40 minutes, and the blower perhaps 25. In other words, I roughly approximated a 1C discharge test and obtained 91% of the rated capacity.
Perhaps they have degraded 9% already. New batteries degrade rapidly at first.
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1.5 years of likely hard use in high draw devices. It makes sense that your fully charged voltage would have dropped. Especially if you are abusing the batteries like most people with deep discharges and storing them on a charger.
However, it does seem like you are correct that the 40V is marketing. Apparently some manufacturers label their batteries based on nominal voltage and some at charged voltage. (Just as some EVs are advertised at usable battery capacity and others at total capacity)
I found this on the Ryobi 40V:
Ryobi "40V" batteries are standard li-ion cells (3.6V nominal) in a 10S2P configuration. Should come in at 42V (10x 4.2V) hot off the charger, 36V nominal (10x 3.6V), and as low as 30V (10x 3.0V) totally flattened - note that the specific voltages that the BMS permits may well be different.