Matching power supply with battery, and how to connect the two

Elite Override

Senior Member
Jan 4, 2011
I've seen a number of places where a power supply such as is matched up with a 12V 7Ah (or some other capacity) battery. I'd like to use something similar to power my 12V router during load shedding (I've been using a Mecer UPS for about a year but the performance has been very poor, and I'd like to cut out the conversion to and from 220V as I don't need to power any devices besides the 12V router).

So I'm looking at buying the aforementioned charger, along with the following battery:

The charger seems to be rated at 3.2A, and the battery is specced at a 2.4A max charge rate. Does that mean that the battery will just take 2.4A from the charger and run fine, or will the charger damage the battery? Does it matter if it is a gel battery or a standard lead acid battery from the charger/power supply's perspective?

Additionally, I assume that the polarity matters when connecting the charger to the battery - is there a guideline to indicate how the wiring should be done? For the output side I can check the current polarity on the router power supply and compare the output with the wiring I do on the output side of the Sherlotronics power supply with a multimeter to make sure they're the same, so that's not an issue.

Thanks for any help.