Yes it is essentially the same thing. Some batteries are designed for standby use - others for cyclical use. The charger maintains either at a 'float' voltage when fully charged & no current being drawn. Some chargers have a secondary setting which drops the float charge a little lower after it has been on float for a preset time. On my Victron mains charger this is referred to as 'Storage'. Not allchargers have this. Either of those two states could be referred to as 'Standby'
Whilst in either of these 'states' the charger can act as a 'power supply' without dropping battery voltage so long as the current draw is within the charger's rated capability (30amps in my case).
I have Victron 10amp & also 30amp chargers. You can set all the settings at all stages of charging to the voltage you want. I have left them on the default settings.
Nice bit of kit the Victron 30amp charger, but the Bluetooth range is a lot less than the 10amp charger, for whatever reason.
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'Float' is still a part of charge equalization where the lead grids are still being chemically altered. 'Storage' is a tiny amount of voltage, but a lot of current less than Float and will give a longer battery life if the battery is actually just stored with no load at all.
Battery charge technology has changed enormously in the past 2 decades. Charge computers these days keep track of acceptance rates, self discharge rates and load cycles to optimize the maintainance regime. Do NOT mix battery types or ages on a charger. When you replace a battery bank be sure to tell the computer its time to relearn the battery charactoristics rather than continue to apply what it has learned about the state of the old bank.
If your charger is more than 10 years old consider upgrading it at your next battery replacement. Or consider changing technologies; LiPo is expensive, but with low mass and voltage hold up to 90% draw down (lead acid should never go below 50%) and many more charge/discharge cycles they are really viable for full time use.
bye
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