I just bought my first deep-cycle battery. Spec page is here and datasheet is attached. It will mainly be sitting open-circuit in an office, until there's a power cut, whereupon it will be plugged into an inverter and used to power some electronics; then it will get recharged when the power comes back on.
My first question is, since they provide a voltage range for charging (14.6-14.8V), should I go for the top (14.8) or bottom (14.6) of that range? What if I use the more conventional 14.4V? Or does it not matter? My charger is fully programmable so I can set any absorption voltage needed, I just need tips on maximising performance and life. I'm familiar with battery university BU-403, but that doesn't address this question.
Second, and more importantly, what should be the condition for terminating charge? It's not listed anywhere in the datasheet as far as I can tell. Some resources say to keep charging at absorption voltage (14.xx) until current decays to 3-5% of C20 (which for this battery would be 3% x 36Ah = 1.08 Amps). Again, my charger is fully programmable so I can set any termination current for end of charge (I won't be using float charge, I will simply stop charging at that point and put battery in storage) - I just need some advice on what to set.
So far, I've been using 14.4V as Absorption voltage, 10A as initial/max current (for bulk phase) and 1A as termination current. When I do that, by the end of charging I can hear a very very faint sound coming from the battery when I press my ear right up against it - the sound a flooded battery makes when it's bubbling, only with this sealed battery the bubble-popping noise only happens once every couple seconds. The battery doesn't warm up at all at any point of charging, and the terminal voltage is 13.1V the next day after removing surface charge with a light load. The absorption phase takes about 2 hours.
My first question is, since they provide a voltage range for charging (14.6-14.8V), should I go for the top (14.8) or bottom (14.6) of that range? What if I use the more conventional 14.4V? Or does it not matter? My charger is fully programmable so I can set any absorption voltage needed, I just need tips on maximising performance and life. I'm familiar with battery university BU-403, but that doesn't address this question.
Second, and more importantly, what should be the condition for terminating charge? It's not listed anywhere in the datasheet as far as I can tell. Some resources say to keep charging at absorption voltage (14.xx) until current decays to 3-5% of C20 (which for this battery would be 3% x 36Ah = 1.08 Amps). Again, my charger is fully programmable so I can set any termination current for end of charge (I won't be using float charge, I will simply stop charging at that point and put battery in storage) - I just need some advice on what to set.
So far, I've been using 14.4V as Absorption voltage, 10A as initial/max current (for bulk phase) and 1A as termination current. When I do that, by the end of charging I can hear a very very faint sound coming from the battery when I press my ear right up against it - the sound a flooded battery makes when it's bubbling, only with this sealed battery the bubble-popping noise only happens once every couple seconds. The battery doesn't warm up at all at any point of charging, and the terminal voltage is 13.1V the next day after removing surface charge with a light load. The absorption phase takes about 2 hours.
Attachments
-
595.9 KB Views: 2