Ebike battery 36V - charging current

I am in the process of purchasing a new battery for electric bike, from the old battery I have charger 42V, 1.35A. I'll buy a battery that has a 36V voltage. Do I have to buy a new charger with a proper charging current or charging current is not that important?

Battery will be Li-ion, I'm still not sure which cells will be in the battery.

A so called 36 volt battery actually charges to 42 volts. (i'm assuming you meant the voltage not the current?)

I really thought about the current, I know that the charging voltage for the 36V battery is 42V.

Then it becomes a matter of how big the battery is, and how fast you need it charged, which also becomes a matter of how cold it is when charging, as low freezing type temps for a battery need slower charging... But the current isn't as important as the voltage unless it's a tiny battery.

It is 14Ah battery, the charging time is not so important for me because it will always be charged overnight and the temperature will always be about 20°C (68 Farenheit).

Charging current of 1.4 amps is fine. Might be a little slow for a bigger battery. My first 36V battery came with a 2.0A charger. The last two 36V batteries I bought, they threw in these tiny 1.4A chargers. Actual output is around 1.1A.

Yes, it would take almost 14 hours to fill up a 14AH battery with them. I'm a worry wart and never charge overnight. I put the charger on a timer if it's going to take more than 4 hours.