What about electric mowers and outboards?

I can't make a case for or against the one I posted, just passing it on.

I've used an Ego brand cordless electric lawnmower for years and it's still going strong. Lawn is on the small side though (100' x 25').

I agree that 18 volts is too low, but if you make the necessary attitude adjustment, then a 24+ volt mower can work fine. We have a large yard, in many sections, so while the B&D CMM mower (20+ years old, now) needs two charges to do it all, my housemate still enjoys using it. She's going to be heartbroken when it dies - assuming that she does indeed outlive it.

I was pretty satisfied with the Mikita 36v(two 18v batteries in series) self propelled 21" walk behind mower. For $499 it came with 4 5ah batts and held all 4 but you'd have to physically take 2 out and replace them with the onboard spares. Mikita also makes one where all 4 batteries are in use, 2 parallel 2 series for again 36v but that one has about 20 min less runtime total, I believe it's because it's more the professional model and has a steel deck and probably more power than the $200 less priced one. All in all while not as powerful as a ICE version, it was perfectly usable for a normal-sized yard and you didn't let the grass get real high or try and mow when the grass was wet or very thick. In those cases the pro model would probably be a better choice. Both models came with the same sized 5ah batteries and 4 of them. The more expensive model may have come with a faster dual charger too, that or it's an option to purchase,

jjeff said:

I was pretty satisfied with the Mikita 36v(two 18v batteries in series) self propelled 21" walk behind mower. For $499 it came with 4 5ah batts and held all 4 but you'd have to physically take 2 out and replace them with the onboard spares. Mikita also makes one where all 4 batteries are in use, 2 parallel 2 series for again 36v but that one has about 20 min less runtime total, I believe it's because it's more the professional model and has a steel deck and probably more power than the $200 less priced one. All in all while not as powerful as a ICE version, it was perfectly usable for a normal-sized yard and you didn't let the grass get real high or try and mow when the grass was wet or very thick. In those cases the pro model would probably be a better choice. Both models came with the same sized 5ah batteries and 4 of them. The more expensive model may have come with a faster dual charger too, that or it's an option to purchase,

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Common problems for some DIY homeowners.

$499 is a bargain for a Makita. That's more like a typical price for 2 or 3 of their batteries alone.

LeftieBiker said:

$499 is a bargain for a Makita. That's more like a typical price for 2 or 3 of their batteries alone.

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Agree, I believe the cost of 4 5ha genuine 18v Makita batteries along with a dual charger might even be more, it's crazy how much individual batteries can cost, OEM ones anyway. Generic ones of Amazon can be a fifth of the price but after a bad experience with one, very hard to get it to charge if the batteries get much lower than 50%, I'm only sticking with original batteries and not the knock-offs.

Yes, the Chinese clone batteries are almost always worthless, and when they aren't, the capacity is still less than advertised. Watching for OEM batteries on sale or with special offers is best.

I have several EGO tools a self propelled lawn mower, string trimmer, blower, and edger. The oldest is the lawn mower at 4 1/2 years. The 7.5 ah battery is still going strong. I never store the batteries at 100% charge, always between 20% and 60% in our basement where it is cool in the summer. Just as 100% charge is bad for a EV battery it is also bad for any LION battery.

When I purchased the lawn more I was surprised at how much more powerful it is than our older corded mower. Being older myself, I really appreciate the self propelled feature. I am happy with all of the tools except the string trimmer. I have had problem with the line getting caught. Then I have to open up the housing and re-thread the line. I have read some reviews where others have had a similar problem. Other than that the trimmer works well. I also like that the batteries work with all of these tools. Sometimes when the grass is taller than usual the 7.5 ah batter will run down, and then I put in the 5 ah battery from the blower to finish the lawn.

Again, I make sure that the batteries are never left sitting at 100%.

bmw said:

Again, I make sure that the batteries are never left sitting at 100%.

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Thats probably a good idea but one I never abide by
For one, I know of no charger that stops at anything other than 100% and another, I like the battery being charged up all the way when I go to use it, it's not convenient to have one battery die and then have to charge another before using it. Now I know if I somehow charged the stored battery to say 80% I wouldn't have to charge it before use but then I wouldn't have a fully charged battery to use.
I guess the 80% would be fine for tools lesser used like a drill where I basically never need the full capacity when using, heck most of the time I probably just use it for screwing something in or drilling a single hole and it goes back on the shelf, but for things like my leaf blower where I frequently use it until it stops(it has a circuit where it stops when the batteries get low and doesn't draw the battery down to nothing like my drill) I really want the 100% capacity.
I guess if I were to somehow know I'd be storing a particular battery for months it would be good to have stopped charging it before 100% but frequently I just don't know when I'm going to use it again or particularly I don't know if I'll need 50% or 100% of the battery. The chargers would also need to have a "long life" or partial charge option built in to make it feasible for me, no way I'd really easily know just how charged the battery is, I guess other than the rather crude 4 LEDs when you push the button on my newer Makita batteries(many are older and lack this nice feature) and note when charging the button always shows full so I'd have to take it off the charger, wait say a minute for things to normalize and then push the button, to know in 25% increments just how full the battery is.
Easier said than done IMO trying to stop charging at anything other than 100%, at least with the current chargers, but I do agree it's probably a good idea, particularly for batteries that will sit for months after charging.

For one, I know of no charger that stops at anything other than 100%

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Makita chargers and charger clones don't stop at 80%, but they let you know when a battery reaches it: you get both the red and green lights on together. I wish they would add an option to actually stop charging there. (Maybe this would sell more of the real chargers, instead of the much cheaper clones with identical features.) As it is, I usually charge to 100% if I don't catch the 80% warning, then run the tool for a minute before putting it or its battery away.

LeftieBiker said:

For one, I know of no charger that stops at anything other than 100%

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Makita chargers and charger clones don't stop at 80%, but they let you know when a battery reaches it: you get both the red and green lights on together. I wish they would add an option to actually stop charging there. (Maybe this would sell more of the real chargers, instead of the much cheaper clones with identical features.) As it is, I usually charge to 100% if I don't catch the 80% warning, then run the tool for a minute before putting it or its battery away.

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Thanks for the tip. I've seen the red and green light on, on occasion but didn't really know what it meant, The symbols Makita gives on their chargers are non-decipherable IMO and the manual isn't much better, like it's meant for too many languages and isn't clear in any of them
If I do see the red and green lights on at the same time I'll unplug the battery(if I don't need a full charge) but truthfully 98% of the time I charge the batteries I just put them in the charger and walk away, returning later when it's fully charged. I do try to not leave the battery in the charger overnight(coming from a Leaf where that isn't a good practice) although truthfully I don't know if it's anything to fret about. I'm pretty sure it's probably not good to leave the batteries on the charger and plugged in indefinitely but even that I'm not sure of. I'm pretty sure it led to an early failure of some of my NiCad batteries but am not sure if it hurts Li batts but as it must waste some electricity I always unplug the battery and charger when done charging. Also might save some wear and tear on the charger itself, especially from power surges and such.

It used to be commonly thought that NiMH batteries love heat, but in reality ALL batteries do better if not kept warm or hot. This is muddied by the fact that some manufacturers, eager to have their batteries perform well, say that it's fine to leave them on the charger. With smart chargers that switch to an occasional float charge that's ok, but if the battery stays warm on the charger, it's better to not leave it there.

They had a little piece on an E-boat on our local FOX9 news last night. It was about a company that was renting an E-boat. A party-type boat and were touting its quietness and lack of oil/gas to get in the water and also the fact that it didn't really produce a wake, something people are starting to worry about more and more. They did warn its top speed was something like 7mph so to not rent it if you wanted to go fast but it looked pretty cool for slow crusing. It held up to 12 people and had a nice canopy for the sun. They called them Duffy boats? and they could be rented by the hour or day on a larger very popular lake in my city, Lake Minnetonka.
https://www.electricshores.co/
https://duffyboats.com/
https://www.fox9.com/video/1096876
After watching the video it seems the top speed is more like 5-6mph and rated run times are not at the top speed so maybe more like 3-4mph?? yes that is a slow cruise funny how they always like stretch things. I do kind of wonder how much wind speed effects top speed, although I'd guess water drag is 95??% of the loss so maybe a 20mph headwind wouldn't really slow down the top speed......I hope so as I'd hate to be going 13mph the wrong direction if I wanted to drive dead on into a 20mph wind!
I searched but couldn't find anything talking about it's battery chemistry or Ah but they say 6v deep cycle batteries so I assume they are old-fashioned lead-acid batteries :? the motors look to be 48v DC and the ones I looked at used 16 batteries! so either they are paralleling them but probably using some sort of inverter to step it down and control speed. No relays like my old electric Renult Dalphine that used 12 6v lead acid batteries and relays to control it's speed
Kind of surprised and disappointed a boat in this price range would use old Pb technology instead of Li........ though I suppose weight might not be a big concern but still.

Those Duffy rental boats are all over Lake Union here in Seattle. They also rent them out of the Kirkland Marina on Lake Washington (closer to where I live). My understanding is that they've been built for decades, which helps explain the choice of lead-acid battery chemistry.

You can buy the Duffy boats for personal use too, and I've read the occasional story of an owner switching out the battery bank to LFP.

Their top speed is fairly low (as you mention), as they are a pure displacement hull, and hull-speed limits kick in fast on something that short (18' - 22'). I hear they are quire maneuverable though, as the motor is attached to the rudder (basically a steerable thruster). I think the motor power is in the neighborhood of 5kW (~6hp).

Bobkart, So how does wind speed affect your speed on a boat? again it can't be a one-for-one as if the top speed was even 7mph, even a 7mph headwind would leave you standing still but I'm sure windspeed is a very minor factor in boats, although paddling against a very strong wind in a canoe can basically leave you standing still even with considerable paddling on the reverse side a tailwind, especially with a makeshift sail can give you some pretty good speed, even not paddling. Although on a car I roughly like to think a 10mph headwind is similar to driving 10mph faster for mpg but again it's probably not nearly that big of an effect but I'd guess more than on a boat.

My impression is that wind has considerably less of an effect on a boat's speed-at-same-power (or power-for-same-speed) than on a car. Of course it depends on the boat, but usually, moving through the water is by far the largest source of drag on a boat. On a very small/thin boat like a kayak, where that 'hydrodynamic drag' is fairly low, sure, wind can dominate the equation at a certain point, due to the somewhat large (in proportion to the bottom) 'frontal area' of the above-the-waterline portion, including the occupant(s) of the kayak.

I would guess that, on one of those Duffy boats, a 10mph headwind would only bring your top speed down by ~1mph (7mph to 6mph). Don't quote me though; it's a complicated situation. I understand (and have applied on occasion) the formula for aerodynamic drag (Fd = V^2 * Cd * A, assuming constant air density), but hydrodynamic drag is a much more complex beast. Still, the point is that the below-the-waterline drag will usually be at least an order of magnitude larger than the part that just moves through air, maybe even two orders.