12thgenusa
Aug 26, 2013Explorer
Are multiple shallow cycles harmful for batteries?
I recently came across this statement in one of the Smartgauge tech papers:
"The more a battery is used the shorter it's life will be. The less it is used, the longer it's life will be.
The only exception to this rule is that batteries should NOT be regularly discharged by only a few percent. Discharging a battery by less than 5% can shorten its life and limit its ability to deliver high currents. This is due to the way the sulphate builds up on the plates which is very irregular during the first stage of the discharge cycle. Either don't discharge the battery at all, or ensure it is always discharged by more than 5%. This is not a particularly well known phenomenon (except by the battery manufacturers) and could be the genesis of the urban folklore/myth of "the batteries need to be worked"."
What are the implications of this for a solar charging system? When not in use, my trailer sits day after day with the solar controller in float. The batteries discharge a small amount overnight due to parasitic loads then recharge the next day--probably 1% or less. Is this more harmful than disconnecting the batteries for several weeks or a month and then top charging? Another option is to leave the batteries connected to the solar charger, but disconnect power to the trailer. Or is this not what the article is about and it doesn't really matter at all?
"The more a battery is used the shorter it's life will be. The less it is used, the longer it's life will be.
The only exception to this rule is that batteries should NOT be regularly discharged by only a few percent. Discharging a battery by less than 5% can shorten its life and limit its ability to deliver high currents. This is due to the way the sulphate builds up on the plates which is very irregular during the first stage of the discharge cycle. Either don't discharge the battery at all, or ensure it is always discharged by more than 5%. This is not a particularly well known phenomenon (except by the battery manufacturers) and could be the genesis of the urban folklore/myth of "the batteries need to be worked"."
What are the implications of this for a solar charging system? When not in use, my trailer sits day after day with the solar controller in float. The batteries discharge a small amount overnight due to parasitic loads then recharge the next day--probably 1% or less. Is this more harmful than disconnecting the batteries for several weeks or a month and then top charging? Another option is to leave the batteries connected to the solar charger, but disconnect power to the trailer. Or is this not what the article is about and it doesn't really matter at all?