battery lawnmowers

greasepalm

Friend is looking for info a battery powered easy push lawnmower and thought i would ask here to see if any replies.Better state large grass area and ones i quicky looked at had a 2.0 ah battery and no mention of how long.

Some come barebones as no battery and charger and bought as extras:eek:

fryup

this is the best value one i could find in ireland, in terms of width of cut and spare battery & charger included (they have cheaper ones too)

i'm getting delivery of one next week so i'll report back

fryup

fryup wrote: »

this is the best value one i could find in ireland, in terms of width of cut and spare battery & charger included (they have cheaper ones too)

i'm getting delivery of one next week so i'll report back

That looks a good one, we have a 36 volt 3 Ah battery in ours and use it for areas that are a pain for the ride on I would estimate that it would cut for an hour continuous depending on the length and whether or not the grass is dry or damp which will take more energy to cut.

Having 2 batteries is great.

Remember, never charge the batteries fully after use, if there's 30-50% in the battery after cutting leave it and only charge it when you need to use it next time. Best to store with 30-50% charge. This should ensure the batteries last a long time. They're not like Nicads either, you do not need to run them down to condition them the odd time or definitely don't run them completely flat as a way of conditioning, they have no memory effect.

Lithium batteries don't like to be at a high state of charge for long periods, storing at 100% for the Winter is a major no no.

fryup

memory effect?

what that in layman's terms

fryup

fryup wrote: »

memory effect?

what that in layman's terms

In the old days of NiCd batteries, if you didn't run them completely flat or use the chargers discharge function.

NiCd cells didn't like being only partially discharged and recharged again they would loose capacity if they weren't ran completely flat, they would use the smaller used capacity over time, Lithium cells are the complete opposite they don't like being fully discharged or fully charged, the sweet spot is around 30-70% but of course if you need all the charge then use it.

fryup

and what type of battery does the one i linked to have? - it doesn't seem to say

fryup

fryup wrote: »

and what type of battery does the one i linked to have?

Lithium, great batteries these days. Without them we wouldn't have electric cars

fryup

a good mineral to invest shares in? if electric cars are the future?

fryup

fryup wrote: »

a good mineral to invest shares in? if electric cars are the future?

No idea, as always, depends on current share cost and how much it will rise in the future.

fryup

fryup wrote: »

this is the best value one i could find in ireland, in terms of width of cut and spare battery & charger included (they have cheaper ones too)

i'm getting delivery of one next week so i'll report back

Update: i've used it twice and very disappointed with it:(

the roller for the stripes came off, the collection box keeps falling off when its half full, but above all else the battery life is poor - 15 to 20 min max

you do get a spare battery but still that's very poor running time imo, in short its tonka toy material

i shall be seeking a full refund forthwith

Wildly Boaring

My father and I have this one between us.
Us it on a few large slopes where ride on can't go.
It's a good mower but not cheap.

Also bought 2 spare batteries.
It the grass is anyway long it drains the 2 batteries in 10mins. But if you keep it short you'd get 25 or 30mins out of a pair.
Travels very well and takes a bit of abuse.

https://www.caulfieldindustrial.com/p/dewalt-dcmw564p2-18-volt-brushless-lawnmower-2-x-50ah-batteries/p-g14238

legend99

I got the Lidl one. It was 90 euro without batteries. They have only had 2ah batteries in stock for months. They do the job. Just. They are supposed to get 4ah batteries back - I asked them - but no sign. The 2ah batteries are about 15 euro each. I think if you buy a 2ah with the charger it is about 25-30 euro. And i think the double fast charger is about 25-30 euro too. It's a small machine. But it works fine. At that price level though you have to commit to cut the grass very frequently. I fly up and down once a week and the 2ah battery just about gets me through the front which I think is about 90 square meters.

I have two batteries but at 15 euro I'll just but a third I think. I also have the battery leaf blower from Lidl which uses 2 batteries (the original l reason I had batteries at all) but again you need to fly up and down with it. Use it on full power and you have only a couple of minutes of life. If they ever get the 4ah batteries back I'd probably buy 2 of them and one of the fast chargers. In the short term I might just buy 2 more 2ah. So in many respects that maybe points towards spending more than planned - so maybe a more expensive kit would have been better from day one. The upside of most of them is that the batteries can be used across that given range - and the individual tools are the cheaper as you buy them without battery.

Bottom line. If you buy a set-up with smaller capacity battery be prepared to buy a few extra batteries or else commit to cutting once a week and to put the boot down when doing so!

Be really careful with these batteries when charging and charge in a fire proof location with a smoke alarm near by. Most batteries are fine but an internal failure can happen. The same goes for e-bike and e-scooter batteries, never charge without basic protection such as a smoke alarm near by and do not charge near anything flammable.

Also, when finished with the batteries charge only to 40-50% not more, batteries are stressed the longer they're kept at higher charge % or too low, Lithium batteries that is, then when you need it next time, charge up only before you intend to cut the grass. This should see you get a good few years from the battery. And never store a Lithium battery over the winter fully charged.

Best if you have any decent lawn at all to get 4 Ah batteries or larger if possible and get two.

fryup

Wildly Boaring wrote: »

But if you keep it short you'd get 25 or 30mins out of a pair.

https://www.caulfieldindustrial.com/p/dewalt-dcmw564p2-18-volt-brushless-lawnmower-2-x-50ah-batteries/p-g14238

just to clarify, is that 25/30 mins for each battery or between the pair?

Wildly Boaring

fryup wrote: »

just to clarify, is that 25/30 mins for each battery or between the pair?

Between the 2 batteries. Now that's walking at full tilt with short grass. You cover plenty of ground.
We've 6 batteries between us I think. Over 100 quid a battery.

My next door neighbour has a lidl or Aldi one. It covers surprising little ground. But he always skins the gtound

fryup

between 2??? so you only get 15min per battery??....but that's very poor esp from a quality make like DeWalt ..i'd be expecting 45min per battery esp at that price

Dempo1

fryup wrote: »

this is the best value one i could find in ireland, in terms of width of cut and spare battery & charger included (they have cheaper ones too)

i'm getting delivery of one next week so i'll report back

I look forward to a review as I too have been wondering about taking the leap to this type of mower. My biggest worry would be how are batteries affected (if at all) over the winter months with little or no usage?, I suppose its all about insuring proper dry storage? No doubting 2 batteries a big plus

fryup

^^^^^^^^

go to post 10

Wildly Boaring

fryup wrote: »

between 2??? so you only get 15min per battery??....but that's very poor esp from a quality make like DeWalt ..i'd be expecting 45min per battery esp at that price

It takes a pair at one.
5Ah batteries.

Dad mows a 100m bank with it. Say 7 runs.
Then the verge outside the house (0.5 acre site) and the verge next door, same. Both 4 runs.
Mulches it all

If the grass the heavy I've used the 6 batteries
But it was light last week. Used 2 and 2 halves. So 3 but you'd have to own 4 batteries or stop and recharge your 2

Wildly Boaring

Dempo1 wrote: »

I look forward to a review as I too have been wondering about taking the leap to this type of mower. My biggest worry would be how are batteries affected (if at all) over the winter months with little or no usage?, I suppose its all about insuring proper dry storage? No doubting 2 batteries a big plus

The batteries are removable. Put in kitchen press for winter

fryup

Wildly Boaring wrote: »

So 3 but you'd have to own 4 batteries or stop and recharge your 2

so that mower takes two batteries at a time?? and you say you bought spare batteries at 100 quid each?? sure that's extortionate

this one here is much better value, wider cut and the battery last for 45 mins +

greenworks 80volt

Wildly Boaring

fryup wrote: »

so that mower takes two batteries at a time?? and you say you bought spare batteries at 100 quid each?? sure that's extortionate

this one here is much better value, wider cut and the battery last for 45 mins +

greenworks 80volt

2 came with it. But the mower was 6 or 7 hundred.
The spare batteries are nearer 150 than 100
We had 3 others between us previously.
Bougth 1 more.

We have a load of DeWalt tools between us so had the 3 batteries. We'd have bought another 1 or 2 batteries anyway.

We've 3 drills, Skil saw, 2 torches, multitool, grinder, impact driver, impract gun......

45 min for the other one probably after a dry week and cutting a cm of grass.

The DeWalt is a very well built mower. We use it for very rough ground. Not gardens. Been doing it for 5 years.
You need to be realistic with charge in these things.

My father has a ride on for the garden. This is for all the other stuff

Dempo1

Dempo1 wrote: »

I look forward to a review as I too have been wondering about taking the leap to this type of mower. My biggest worry would be how are batteries affected (if at all) over the winter months with little or no usage?, I suppose its all about insuring proper dry storage? No doubting 2 batteries a big plus

Winter storage will have absolutely no effect but "ONLY" if you store them around 40-50% charge do not ever store a lithium battery at full or empty charge as this can greatly degrade the life of the battery. It will still work in the Summer but you will not get a long time from the battery if you store a Lithium battery fully charged for an entire Winter. Modern batteries should last years if you do this + after use charge to again, 40-50% and charge up to 100% only before you use it, night before is fine. Batteries are stressed more the longer they are at high charge % or very low %.

Be really careful with these batteries when charging and charge in a fire proof location with a smoke alarm near by. Most batteries are fine but an internal failure can happen. The same goes for e-bike and e-scooter batteries, never charge without basic protection such as a smoke alarm near by and do not charge near anything flammable.

Wildly Boaring wrote: »

The batteries are removable. Put in kitchen press for winter

Storing in the shed is fine, batteries like to be stored in a cool environment but never charge a battery if it's anywhere near freezing in the shed, bring the battery in and let it warm up over night then charge the next day.

Also, leaving a Li battery in the press is not a good idea they must be stored in a fireproof location with a smoke alarm near by. These batteries have internal protection systems and they can fail but there is absolutely no protection from a rogue cell failing causing thermal runaway or fire.

It's not the Ah that matters but the Watt Hrs.

What voltage are your batteries folks ? volts and Ah ?

Multiply the volts by the Ah and you get the Watt Hrs, the Watt Hrs is the total storage you have in the battery, the more Watt Hrs the more run time.

It wouldn't surprise me if some of those batteries are over rated, it's well known that manufacturers do this, it's possible.

Cutting grass before it gets long is a good idea.

By the way, a cold battery will also have less energy and higher internal resistance so it won't be able to provide the same level of power and can sag, what I mean by sag is that under load the voltage will drop higher than normal and at a certain point in the charge that could be enough to trip the battery protection, this is emphasised with cheaper quality batteries, So make sure your batteries are room temp before charging and use, they like to be stored cold though.

Darwin

I have some Ego gardening equipment + batteries and while expensive it is excellent piece of kit for a larger garden. The batteries themselves automatically discharge to 30% if left unattended for more than 30 days so one less thing to worry about. The largest battery I have (7.5A @ 56v = 420 Watt hrs) is 3 years old at this stage and still runs for about 50 minutes.

Wildly Boaring

The DeWalt are all 18V
5Ah

fryup

Deleted User wrote: »

It's not the Ah that matters but the Watt Hrs.

What voltage are your batteries folks ? volts and Ah ?

Multiply the volts by the Ah and you get the Watt Hrs, the Watt Hrs is the total storage you have in the battery, the more Watt Hrs the more run time.

so how do calculate watt hours into running time??

mine is 60v x 2ah = 120watt hrs (but the actual running time is 35 minutes'ish)

blackbox

[Deleted User] wrote: »

Remember, never charge the batteries fully after use, if there's 30-50% in the battery after cutting leave it and only charge it when you need to use it next time. Best to store with 30-50% charge. This should ensure the batteries last a long time. They're not like Nicads either, you do not need to run them down to condition them the odd time or definitely don't run them completely flat as a way of conditioning, they have no memory effect.

Lithium batteries don't like to be at a high state of charge for long periods, storing at 100% for the Winter is a major no no.

I have a golf trolley and a robot mower with lithium batteries. Both manufacturers recommend storing them fully charged. Including over winter.

Can you please let us know where you got this advice.

Darwin

Darwin wrote: »

I have some Ego gardening equipment + batteries and while expensive it is excellent piece of kit for a larger garden. The batteries themselves automatically discharge to 30% if left unattended for more than 30 days so one less thing to worry about. The largest battery I have (7.5A @ 56v = 420 Watt hrs) is 3 years old at this stage and still runs for about 50 minutes.

That's fantastic, glad to see some companies are paying attention ! Need Ebike and E-scooter manufacturers to do the same.

blackbox

blackbox wrote: »

I have a golf trolley and a robot mower with lithium batteries. Both manufacturers recommend storing them fully charged. Including over winter.

Can you please let us know where you got this advice.

I Researched this for a long time when I was building ebikes and it's well known and understood that leaving li batteries fully charged or discharged for long periods can and will degrade their life.

This advice to leave li batteries fully charged for storage is very bad.

There's lots of knowledge about Lithium batteries in the link below but also review university studies and papers.

https://batteryuniversity.com/articles

Also check here.

https://batteryuniversity.com/article/bu-702-how-to-store-batteries

Li-ion has higher losses if stored fully charged rather than at a SoC of 40 percent.

fryup

fryup wrote: »

so how do calculate watt hours into running time??

mine is 60v x 2ah = 120watt hrs (but the actual running time is 35 minutes'ish)

To get the running time you'd have to know what power the mower is pulling and the easy way to do this and one that might be pretty useful is to attach one of these at the motor controller, between the battery wires and controller. that's the silver box that looks like this.



The power monitor looks like this.

https://www.amazon.co.uk/Precision-Analyzer-Consumption-Performance-Backlight/dp/B07M5XD4G9/ref=sr_1_2_sspa?dchild=1&keywords=battery+monitor&qid=1624203742&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExM0JUMllOS1FYTlAzJmVuY3J5cHRlZElkPUEwMDMyNDkwWTEyNlFCVDBBMllaJmVuY3J5cHRlZEFkSWQ9QTA0MzUyMTAzRlVRMUtGSFpMRkxZJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ==

This voltage/power monitor will tell you exactly how many AH is being pulled from the battery.

But generally the voltage x ah = watt hrs, the more you have the longer the device runs, just knowing the Ah alone is useless, for example.

24v 5 ah = 120 Watt hrs

52v x 5 ah = 260 watt hrs

Other factors that might greatly influence battery run time are, higher internal resistance = poorer quality, basically if the battery is getting hot this is a key indicator of high internal resistance. High temperature might also cause the battery to cut out before all the energy is used, as the battery ages it will get hotter and hotter.

Try let the battery cool after fully charging it before cutting the lawn, then let it cool before charging it, higher temperature shortens the life of the battery, store in a cool location.

If the battery feels warm on the outside then inside the casing the actual cells could be hot to roasting.

Always try find a battery mower who's charger has a build in fan to cool the battery as it's charging.

Wildly Boaring

When batteries come out of the DeWalt mower they are roasting.
Always let cool before charging but did keep stored at 100% until recently

Darwin

The Ego chargers have built in fans and the batteries themselves have a specially designed casing to keep the cells cool. My fast charger failed inside warranty which wasn't great though!

Wildly Boaring

Wildly Boaring wrote: »

When batteries come out of the DeWalt mower they are roasting.
Always let cool before charging but did keep stored at 100% until recently

that kind of heat is certainly going to reduce the life of the battery a lot faster, if they're hot through the plastic casing imagine what the cells are like inside ?

Were they always roasting even from new ?

The batteries usually get warmer as they age and if they weren't as hot when new and they are hot now that's a clear indicator that internal resistance has increased a lot which is a clear indicator to aging.

It's also a good idea to let the battery cool after charging, even though it might not seem warm from the outside it could be warm inside.

Wildly Boaring

I've rarely noticed them hot using a drill or Skil saw. But with the mower yes I think they've always been hot.

Talking to my father about this today. He reckons one of his 2016 batteries is no use by now

Wildly Boaring

Wildly Boaring wrote: »

I've rarely noticed them hot using a drill or Skil saw. But with the mower yes I think they've always been hot.

Talking to my father about this today. He reckons one of his 2016 batteries is no use by now

Sounds like it's time to change.

Springwell

We've an Ego with a 7.5Ah battery, tackles 0.75-1 acre of long/rough meadow grass no bother in a charge (depends how wet/long, if left very long you need a charge for the last bit) Pricey though!

The good mowers with good batteries are usually pricey. But you don't have to worry about maintenance and they're much easier to start than a petrol mower + much lighter.

The technology is improving every year. The self propelled ones will be harder on the battery too.

If looking for a mower always look for higher voltage 36 volt minimum 52 volts or higher even better and highest Ah battery and fastest charger you can buy it's worth it in the long run.

TheBigGreen

Greenworks 80V FTW

TheBigGreen

TheBigGreen wrote: »

Greenworks 80V FTW

I just googled and saw an 80v 4 ah battery that's amazing, progressing much faster than I thought. That's 320 Watt hrs of storage which is twice that of some lower voltage batteries.

The thing about higher voltage is that they should run at lower currents meaning less heat which is always good, current produces heat.

So yeah, always go for the highest voltage you can, at that rate I'd say 52 volts should be the minimum these days of they have 80 volt batteries now.

fryup

thinking about getting a spare for mine, but can these batteries be sent over from the UK to a private address?? aren't they classed as hazardous material?

or will i have to order one through my DIY store?

fryup

fryup wrote: »

thinking about getting a spare for mine, but can these batteries be sent over from the UK?? aren't they classed as hazardous material?

Yes they can be sent but usually the courier has to be aware and might charge more but where you get the battery might not have this shipping service available .

greasepalm

Interesting read so might as well ask if anyone has replaced a dodgy cell in a power pack and sourced them to fit.

greasepalm

greasepalm wrote: »

Interesting read so might as well ask if anyone has replaced a dodgy cell in a power pack and sourced them to fit.

It's not so easy to replace a cell in a pack and in fact, I wouldn't do it because you have to make sure all the cells have the same internal resistance or they will only perform as good as the weakest cell and it's not going to be easy to match a new cell with an old, certainly a new cell into an old pack is not a good idea.

Springwell

Should have added ours is self propelled and the field is on the side of a hill! Takes a bit more out of it!

Springwell

Springwell wrote: »

Should have added ours is self propelled and the field is on the side of a hill! Takes a bit more out of it!

Yeah will take more out of it alright but bet you appreciate it on the hill !

I have a ride on and I couldn't imagine doing it with a petrol or electric mower on 1 acre, well that's including house and yard and still takes me around 1 hr or little more depending how long it is ( and how often my 2 Sons harass me for spins lol ) but before I got the ride on with the petrol mower, a good wide one, it was talking I think 4+ hrs because I had to empty the box so much it really wasn't practical.

Kaybaykwah

Darwin wrote: »

I have some Ego gardening equipment + batteries and while expensive it is excellent piece of kit for a larger garden. The batteries themselves automatically discharge to 30% if left unattended for more than 30 days so one less thing to worry about. The largest battery I have (7.5A @ 56v = 420 Watt hrs) is 3 years old at this stage and still runs for about 50 minutes.

I totally agree. I bought the Ego mower here in Canada 3 years ago, and it is very satisfactory, I haven't found any negatives, so far.


I hope I don't run into a charger problem like you did after warranty, though.

New Home

Any views on this one?

https://www.lidl.ie/p/great-gardens/1300w-electric-lawnmower/p12668

EDIT: Sorry, wrong thread, I've just realised it has a cable.

fryup

i have this one,

https://www.coopsuperstores.ie/Greenworks-Cordless--60v-Digipro-Lawnmower-With-2ah-Battery--Charger-1776950

first time i used it i got 35min running time off it, used it for the second time today and got 27min working time off it

am i doing something wrong should i charge it the night before i use it?