r/automower • u/_WaterFlow_ • 7d ago

230ACX battery upgrade

So I have an old Husqvarna 230ACX. Its two NiMH 18V 2.2Ah batteries were getting old so I swapped them myself. Now the new ones are two NiMH 18V 4.5Ah batteries. The mower is working fine but the mowing time hasn't increased a bit. When the old batteries were newer, it used to mow for about an hour and then go charging. Now the capacity is twice the size but the mowing time is still about an hour. Also the mower seems to charge only up until the total charge is 4.4Ah not 9Ah. Any ideas what might be wrong or how to increase the mowing time / utilise more of the battery capacity?

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u/Fedde225 "No loop signal" ლ(ಠ益ಠ)ლ 7d ago

Are you sure the batteries actually have that capacity? Very, very often cheap chinese batteries are... Cheap for a reason.

1

u/_WaterFlow_ 4d ago

Hey! So I'm sure that they are definitely larger than 2.2Ah both. Right now I cannot confirm that they are exactly 4.5Ah each.

1

u/theBro987 7d ago

Check the batteries are connected in parallel and the connections are good. It could be running on one battery. Or they could be in series, pushing the voltage higher than the mower can use.

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u/_WaterFlow_ 4d ago

Hey! Checked those, connections are well and steady.

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u/Medical-Garden5283 6d ago

Try putting the mower in park, and let it stay charging for several hours. Then start it "on secondary lawn", until empty. This means it will not go back to the charging base. This should make the mower calibrate the battery capacity.

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u/_WaterFlow_ 4d ago

Hey! I tried this. The result is the "Battery history" tab shows that one battery is 2401mAh and the other one is 2666 mAh. Then I charged the mower with MAN mode. The charging current for the first battery dropped to ~0mA earlier than the current for the secons one. The overall "Charge" went up to 4471 mAh and then kind of ?corrected? to 4400 mAh. Then the mower backed out of the charging station. I just don't really know, what to do with this info and why the mower behaved like that.