Battery information

Thread Starter


Joined Jan 13, 2010
Probably some of the most basic questions you guys could think of, but I'm not showing any results on google or here.

it's a 12V 5AH SLA battery.

It says

Type |Voltage regulation|initial current|
Stand-by-use| 13.5v-13.8v | No limit
Cycle Use | 14.6v-150.v | 1.5A max

What does all this mean?


Joined Jul 17, 2007
I've re-formatted your text a bit; if you use the [ CODE] [ /CODE] blocks (no spaces) around column-sensitive text, the board won't goof up the formatting. Compose in Notepad beforehand.
Rich (BB code):
Type         | Voltage regulation |initial current|
Stand-by-use |  13.5v-13.8v       | No limit
Cycle Use    |  14.6v-15.0v       | 1.5A max
Basically, it means that your battery can be float-charged at 13.5v to 13.8v without a current limiter when it's charged up.

If it's been discharged, it should be charged up to 14.6v to 15v at a 1.5A maximum current for the charging rate. Then you float charge it at 13.5v-13.8v to keep it ready for use.


Joined Oct 2, 2009
1. Means that you can hook a discharged battery to a constant-voltage power supply set to 13.5 to 13.8V for ever. You do not have to use any current limiting, the battery will charge slowly, and then be "floated". This will not damage the battery. This is not the fastest way to recharge the battery, but it will eventually get it recharged...

2. Means that you can hook a discharged battery to a constant voltage power supply set to 14.6V to 15.0V, but the supply has to be current-limited to 1.5A max. When first connected, the battery will pull-down the power supply's voltage (due to the supply being current-limited). As the battery accumulates charge, the voltage will come up the set voltage (14.6 to 15V), and the current into the battery will begin to decrease downward from 1.5A. The specified current-limit is to prevent the battery heating excessively. The "Cycle Use" implies that this cycle should be terminated when the battery charging current drops to a small value, like 10% of the 1.5A limit (150mA), at which point the supply voltage should be set to (1), above... This recharges a battery much faster than (1), above.

There are microprocessor-controlled chargers that mechanize the above algorithm. This is called a three-step charging algorithm (initially current-limited, then voltage limited, current drops, revert to lower float-voltage). See Figure 2 in this document.