Well, all battery types I know of are charged in the same way. Constant current, then constant voltage. But the point where you switch from CC to CV is different for all battery types. A lead acid charger switches at 2.3V per cell to constant current. Whereas the voltage for LiPo batteries will be 4.2V per cell.
You shouldn't use that charger, unless you want to cause a fire.
While writing the next paragraph I noticed how dangerous it will be to use that charger. There are too many things to consider. The underlined numbers are just rough guesswork!!
If you really, really have to use it, one time only. And you can set the voltage of your charger in a range of 40V-60V. You could hook up a multimeter in series to measure the charging current. Then set the charging voltage to 1/2 or 1/4 of the final 54.6 voltage. Immediately measure the current which has to be at most 2-3A. If it's higher, the voltage is too high. This must be verified in a couple of seconds, 10 at most! Then every 5-10 minutes check the battery temperature (cool enough to touch), and check that the current is below 2-3A. You should also disconnect the charger every 5-10 minutes, and measure the voltage of the battery pack to ensure that it's below 54.6V. The voltage of the pack discharged is 3.4V * 13 = 44.2V. You can't check the voltage of the pack while the charger is connected (will give you the wrong reading). The range, 44.2V -> 54.6V gives you an indication how far the pack is charged. When the charging current reaches let's say 1A-1.5A, you can increase the voltage in small steps to increase the current. When you reach 50V you should start to decrease the charging current to 0.5A
It's very, very important, that you regularly check the packs voltage, check the current, check the temperature (50°C max).
So many underlined numbers, this is not good. I'd take the risk, outside, with a huge bag of sand to extinguish any fire (water only makes it worse!!). On an inflammable ground, with safety goggles, heat resistant gloves, gas mask ....
If you want to learn more about the topic google for "charging lipo" that just gave me some nice results!