Understanding the "maximum continuous discharge current" battery specification

[max4296]

Some newbie questions I haven't found clear answers to - please bear with me.
1) So when a 12v battery states that its maximum continuous discharge current is, say, 125 amps/Ah, that means that battery does not like to be discharging 1,500W continuously, and may even shut down or get damaged at that rate?

2) But if you parallel it with another battery of same exact type, does the maximum continuous discharge current double and go up to 250amps?

3) If so, is the reason the max discharge current doubles because the current draw is split roughly evenly between each paralleled battery?

4) And if that's the case, would it be okay to have 125amp terminal mount fuses on each battery? If the total wattage draw exceeds 1,500W, and therefore exceeds the amp rating of each individual fuse, it should not blow those fuses because that total wattage draw will be shared roughly equally between the batteries? Therefore, each individual fuse might blow only when approaching 3,000W draw total on both batteries.

Thanks in advance. Hopefully the way I phrased my questions made sense.

 

[sunshine_eggo]

1) it should survive it, but reduced cycle life may result. Additionally, if the current is a limit of the BMS, running cheap BMS at rated may cause premature failure.

2) If batteries share current perfectly, yes. However, nothing is perfect. I would assume no more than 80-90% of 250A.

3) Yep.

4) No. Running a ruse at its rated current WILL cause it to blow. You want the fuses 1.25X the wire rating in most cases.

 

[DIYrich]

Don't forget surge rating on battery and fuse.