Questions on Newly Bought SP 21inches Lawn Mower

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  • Updated 3 years ago
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1) I also bought trimmer which came with 2.5Ah battery, can I use it in Lawn Mower? If yes, how many minutes It can provide?
2) I have SP version, if I do not want to use self propel mode and push it...would it save me some extra battery life?
3)I have total 0.6 Acre, Will 7.5Ah battery will be sufficient to do the job? (grass is rye and not thick, and no weed)

Thank you very much.
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Hemangi Barochia

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Posted 3 years ago

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No worries. The batteries can be swapped out.  The 7.5 you should get about 45 minutes out of it.  The smaller one about 20 minutes.  
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.6 acres on one charge. Matters how much grass that is which means how much grass vs housed, pavement, ect. I mow double that and i have three 5 ah and one 4 ah and a 20" mower. Takes me about 8 hours. And 10 charges. So no way would on 7.5 ah do your whole yard. Your looking at 3 charges, maybe 2. Also matters if its hilly or not. Hills affect sp battery drain.
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I have the 21" SP and can mow 0.5 acre with the 7.5 ah battery with a little left over under average conditions. I usually mulch with plug inserted. Grass is thick fescue. If the grass is wet or if I'm delayed in cutting, then I get about 75% done on a single charge. I use the SP mode all the time. With rye and minimal heavy stuff, you should be fine.
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Wowsa. Maybe i overlap too much lol. Or that 7.5 ah is just amazing
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2-It will save a little charge time, but it pushes so easy not using SP unless needed becomes habit
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David Cline

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I am with Jacob on this one, unless most of the half acre is taken up with a mansion, finishing the whole lawn without a single recharge would be a miracle.
I also have the SP Ego lawnmower and have .5 acres, too.  I never run out of power...even if the grass is thick or a little wet. I do use the SP feature about 1/2 the time for long runs or on my sloped areas.  I use the mulcher and have Kentucky Blue Grass sod.

I have been VERY happy. I had a Black and Decker (no SP), both mower and weed whip before this. It was getting old so I gave it to my son. I had no complaints about the B&D but the Ego was a marked improvement. So, much I am purchasing the new Power Head and trimmer accessory. I liked that it can use the mower's battery. They sold out fast so I had to wait a few weeks to order mine and another couple of weeks to have it delivered.
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David Cline

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Official Response
The fact that the mower has a variable power motor means that the grass type and mowing conditions are going to have a HUGE impact on the answers to your questions, as you can see from the responses so far. From page 11 of the mower manual:

So to answer your questions:

1. Yes, but using a 2.0 or 2.5 will reduce the mower's performance slightly in the lightest of conditions, and will only yield about 15-20 minutes at best. In heavier conditions you may only get 5-10 minutes of sub-par mowing, not really enough to recharge your 7.5.

2. The difference is fairly negligible in my experience, but in very light mowing conditions perhaps could extend run time a few minutes. But it would be more like a few seconds if the blade motor is drawing anywhere near its 1000w max in moderate to heavy mowing.

3. I have about 1/4 acre and can finish my yard on a single charge with the battery nearly fully depleted on a good day. I would anticipate needing to recharge the battery at least once per mow on a half acre lot, unless you have lots of unmowed areas (flower beds, house, driveway, etc)
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Blue Angel, Champion

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DC, iirc, you are mowing fairly low and in fairly thick Bermuda grass, right? Those conditions would lean towards the lower end of the run time scale, I'd think.
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David Cline

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Yes, bermuda sod (overseeded in the back with some unknown mutant variety I couldn't choke out that is always wet when cut), right now heavily sprinkled with weeds that I can't hold back from the neighboring yards.

Sorry... I forget that everyone here hasn't seen, memorized, and gotten sick and tired of seeing and hearing pictures, videos, and posts about my yard. Kind of like babies on social media.