I have two solar arrays which totals close to 2 kw that I use to charge a 24 v 450 amps flooded lead-acid battery bank using 2 mppt charge controller of 30 and 40 amps.
Will it damage the battery by charging it too fast?
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Those MPPT controllers seem appropriately sized compared to panel capacity. The panels might output slightly more under absolutely ideal conditions, but those are rare.
70A into a 450 amp-hour battery means you would recharge them from zero in 6.5 hours (which you should not ever do, allowing lead-acids to fall anywhere near zero, that is).
So your charging rate is 0.1555 "C", which is high, but still within limits for lead-acid. It may tend to heat up a bit given the fairly fast recharge rate, which may cause high water use. Be careful; use distilled water for makeup water, because if you're frequently adding water, that means any impurities in the water get concentrated fast.
It could not only damage the battery.
As already mentioned, fast charging of non-defective flooded lead acid batteries with high currents is normally no problem - given the charger meets the lead acid charging regime and all cells and charger are working properly - and the room is vented without discharges from static electricity or sparkings, overheating etc.
Otherwise it could become a safety problem. Some lead batteries produce H2 and/or O2 during charging. And in case of defective cells or chargers that do not fail safe.
Both gases are a very explosive combination. The engine room in a car is always vented.
H2 alone has a big explosive limit range, i.e. the percentage interval of H2 concentration in air to yield an explosive mixture is roughly 5 to 75 volume percentage.
For comparison, gasoline has a range of 2 to 10 vol-%.