6 ms·

A kilowatt hour of car battery pack costs ~$150 now. I was looking at battery powered lawn mowers last night, and noticed that a 0.42 kWh battery pack costs $35

by csours 6y ago

A kilowatt hour of car battery pack costs ~$150 now. I was looking at battery powered lawn mowers last night, and noticed that a 0.42 kWh battery pack costs $350[0]. I know that power tool batteries have different requirements than car battery packs, but that base .42 kWh should still be under $100. I feel like this is the printer/razor model, where you sell the base item for cheap, but the consumables cost are extreme. Although, for long lasting durable goods, you have to make money somewhere, as a good battery mower may last a very long time. 0: https://community.egopowerplus.com/ego/topics/kilowatt-hours-kwh-required-to-fully-charge-the-5-ah-battery?topic-reply-list[settings][filter_by]=all&topic-reply-list[settings][reply_id]=20372921#reply_20372921 https://community.egopowerplus.com/ego/topics/kilowatt-hours...

bengale 6y ago
This is something I read a lot when I was looking at getting some Ryobi One+ tools. It ended up being that buying the tools bare was quite reasonable, but getting batteries was extortionate. I ended up getting knock off batteries for a third of the price and they've held up brilliantly. Did bring back memories of knockoff printer ink, I wonder if the tools will start having chips to detect knock offs before long.
xxs 6y ago
No idea which lawnmower battery pack you meant. All of them are 18650 elements with the good ones (3A/h, 30A) like 5$/€ retail price. One of them is ~11Wh (say 3.7V) - to get 420Wh you need 38. So the price looks decent retail one - building it yourself with quality elements would be another 25-30 for housing (pref. some polycarbonate composite) and pcb (quality/balancing charger, etc.) LiIon is a lot more expensive and more energy dense than lead/acid combo commonly found in car batteries. Drag racer may drop the entire car battery, replacing it super capacitors to reduce weight.
- skt5 6y ago
  It's most likely an 56 volt Ego 7.5 Ah battery. I bought mine a few years ago on eBay for $200.
  - csours 6y ago
    Yes, this is the one I was talking about. I looked at retail cells because I was curious and $5 looked about right for retail, but I can't imagine the OEM Manufacturer would be paying that much. My initial uneducated guess before I did any math or looked anything up was that the BOM cost for the battery pack would have been like $50, but $200 seems more reasonable. I guess a $150 markup isn't that unreasonable, but it is a bit of a sticker shock when you compare the cost of a mower bundle [0] to a bare battery pack [1]. Still, the margin seems fat here. I really am of two minds on this, because I realize what the race to the bottom could do here. I don't want a battery pack that would burn my house down. I want a battery pack that lasts a long time (durable over usage cycles). I'd love to hear about your experience with the system if you don't mind sharing. 0. $370 Mower + 5 Ah battery + Charger https://www.homedepot.com/p/EGO-21-in-56V-Lithium-Ion-Cordless-Electric-Walk-Behind-Push-Mower-5-0-Ah-Battery-and-Charger-Included-LM2101/206515766 https://www.homedepot.com/p/EGO-21-in-56V-Lithium-Ion-Cordle... 1. $350 7.5 Ah battery https://www.homedepot.com/p/EGO-56-Volt-7-5-Ah-Battery-with-Fuel-Gauge-BA4200T/308667794 https://www.homedepot.com/p/EGO-56-Volt-7-5-Ah-Battery-with-...
    - xxs 6y ago
      It's US where LiIon is presumed 4V nominal, so effectively 42 elements. Pretty nice margins. Indeed battery pack is where the tool companies make their profit with all of them being incompatible with each other, including Dewalt/Black and Decker (same company different brands) having just a small plastic notch to prevent interchange usage. -- Edit: durability depends on max charge and min/cut off discharge voltage (something like 4.13v/3.3 would be decent) - you can test those with voltmeter easily, temperature the batteries are run at, and discharge current. At around 400 cycles they should be at ~85% capacity.
      - xyzzy123 6y ago
        You can find x to y battery adapters on ebay, in case you found it as annoying as I did.
    - snovv_crash 6y ago
mdasen 6y ago
I think there's a combination of things here, but it's not the printer/razor model. You just don't have to replace the batteries frequently enough for that model. The battery pack should last for years. If you can cut your lawn in one charge and you cut it once a week, you should get around a decade out of it (assuming 500 charge cycles, LiIon batteries are usually 400-1,200 cycles). The battery you're looking at isn't just shrink-wrapped cells. I've seen 1-kWh e-bike batteries around $150 on AliExpress (shipped from China) that are just shrink-wrapped cells with a cable coming out where you're supposed to be knowledgable enough about batteries to make sure you use it safely and not catch on fire and such. This is in contrast to nicely packaged batteries that cost significantly more (like $800 for 1kWh at Luna Cycle). This battery is available when you want it (rather than shipped from China with a month wait), you're paying for the retail availability and service/support/returns, you're paying for knowing that the cells are likely reputable cells from a major manufacturer like Panasonic, LG, or Samsung, and you're maybe paying a little for the fact that it's a product-specific adaptation to fit the lawnmower. However, it doesn't look like they're marking you up much at all. E-bike batteries are a good comparison here. E-bike batteries are a relatively competitive market and the pricing sounds about right for something that's supported, has US distribution, decent quality, not a fire hazard, etc. - $350 for 420kWh. It doesn't really sound like you're getting over-charged. If you want a battery from a well-priced but reputable source, it's not $150 per kWh for batteries of this size. It sounds like they're charging you about what batteries of that size go for. You can certainly search around for ebike batteries and see that despite their being a competitive market there, you're not paying $150 per kWh. Doing a little searching, I can see 1 kWh for $800, 850 Wh for $620, 900 Wh for $600, etc. On Alibaba, I can see some cheaper things, but we're still talking $230 for 600 Wh, $400 for 900 Wh and who knows when they'll arrive or what quality they'll be. The lawn mower company might have a little margin on you, but they aren't over-charging a lot. From what I've seen for US-source e-bike batteries, it's pretty much in-line with my expectations. I've seen 420 Wh batteries a little cheaper (like $275 is the cheapest I've seen) which is cheaper, but you're looking at a slightly more niche product (a battery for a specific lawnmower) and likely looking at a bit more retail markup (like a big box store vs. a no-name online retailer), etc. $350 is pretty competitive and you're going to need to spend it once a decade so the possible $75 margin doesn't seem like much at $7.50 per year. I mean, you could maybe buy an e-bike battery and get it to work with the lawnmower, but I don't see e-bike batteries that are that much better for pricing. I mean, if you buy the lawnmower and it lasts you a decade and you love it, I don't feel like a $75 markup for a second decade on it feels like taking advantage of you. That just feels like retail markup and, frankly, I'd probably trust Luna Cycle more than the retailer I'd never heard of with the $275 420Wh battery. Luna's $460 650 Wh battery would cost the same as a $298 420 Wh battery, assuming the same price per Wh. $50 just doesn't seem bad.
asdff 6y ago
The problem is, ten years after you buy your mower and need to replace the original battery pack, will the manufacturer even make that proprietary shape? If owning an electric mower means buying an entirely new manufactured unit and battery every 10 years, delivered to your door in a shipping container across the pacific, that can't be much better for the environment than using a 25 year old $50 gas mower that's been circling the neighborhood craigslist forever. I just worry with the continual shedding of older technologies for better ones, that we fail to calculate the costs to replace these technologies and the costs to build new technologies as we get blinded by optimism and profit opportunities. The real rub on the environment more than anything else are our rampant consumerism and the globally extended supply lines needed to fuel that insatiable itch.
- csours 6y ago
  Well, there's the CO2 environment, and then there's my personal environment. In my personal environment, I don't want to use a gas mower due to extreme levels of particulate and un-burned gasoline pollution.
- bluGill 6y ago
  Most mowers have a 10 year planned obsolescence lifetime and will die before then. A 25 year old lawnmower probably cost a lot more for the engineering to make it last. Though even then they expect 3 years, but that is using it 40 hours a week so a homeowner doing an hour every Saturday is nothing even over 25 years.
  - asdff 6y ago
    Any simple gas mower you buy off the line today can last practically forever if you just do basic maintenance and store it properly between seasons. They are just pretty simple engine designs that haven't really changed in decades. I used to be a groundskeeper, and as long as we kept the blades sharp and did basic engine maintenance like changing the oil and filter, we could just abuse a push mower all over the golf course for 50 hours a week summer after summer.
    - 6y ago
ip26 6y ago
The batteries are a lot cheaper when you buy them with a tool. I think they make the batteries by themselves expensive mainly to nudge you to buy another tool.
alister 6y ago
> a good battery mower may last a very long time However I’m worried about the availability of the mower’s battery 5-10 years from now. The battery packs have unique shapes, controllers, etc., which might be discontinued or become insanely expensive to replace in the future. If I were to buy a second mower battery as a backup, what would be the optimal strategy for maximizing the total life of my two batteries? Would it be best to: - never use the second battery until the first one dies - alternate between the two batteries - something else?
- ProZsolt 6y ago
  Batteries degrade while in storage and they degrade with every cycle. The best you can do is never store it fully charged. Never discharge it fully. Modern tools never let you do that, but if you store a "discharged" battery it will fully discharge(by self-discharge) over time. The best way is to charge it to 3.7V and then store it and check it at least yearly.

by csours 6y ago

bengale 6y ago

This is something I read a lot when I was looking at getting some Ryobi One+ tools. It ended up being that buying the tools bare was quite reasonable, but getting batteries was extortionate. I ended up getting knock off batteries for a third of the price and they've held up brilliantly. Did bring back memories of knockoff printer ink, I wonder if the tools will start having chips to detect knock offs before long.

xxs 6y ago

No idea which lawnmower battery pack you meant. All of them are 18650 elements with the good ones (3A/h, 30A) like 5$/€ retail price. One of them is ~11Wh (say 3.7V) - to get 420Wh you need 38. So the price looks decent retail one - building it yourself with quality elements would be another 25-30 for housing (pref. some polycarbonate composite) and pcb (quality/balancing charger, etc.) LiIon is a lot more expensive and more energy dense than lead/acid combo commonly found in car batteries. Drag racer may drop the entire car battery, replacing it super capacitors to reduce weight.

skt5 6y ago
It's most likely an 56 volt Ego 7.5 Ah battery. I bought mine a few years ago on eBay for $200.
- csours 6y ago
  Yes, this is the one I was talking about. I looked at retail cells because I was curious and $5 looked about right for retail, but I can't imagine the OEM Manufacturer would be paying that much. My initial uneducated guess before I did any math or looked anything up was that the BOM cost for the battery pack would have been like $50, but $200 seems more reasonable. I guess a $150 markup isn't that unreasonable, but it is a bit of a sticker shock when you compare the cost of a mower bundle [0] to a bare battery pack [1]. Still, the margin seems fat here. I really am of two minds on this, because I realize what the race to the bottom could do here. I don't want a battery pack that would burn my house down. I want a battery pack that lasts a long time (durable over usage cycles). I'd love to hear about your experience with the system if you don't mind sharing. 0. $370 Mower + 5 Ah battery + Charger https://www.homedepot.com/p/EGO-21-in-56V-Lithium-Ion-Cordless-Electric-Walk-Behind-Push-Mower-5-0-Ah-Battery-and-Charger-Included-LM2101/206515766 https://www.homedepot.com/p/EGO-21-in-56V-Lithium-Ion-Cordle... 1. $350 7.5 Ah battery https://www.homedepot.com/p/EGO-56-Volt-7-5-Ah-Battery-with-Fuel-Gauge-BA4200T/308667794 https://www.homedepot.com/p/EGO-56-Volt-7-5-Ah-Battery-with-...
  - xxs 6y ago
    It's US where LiIon is presumed 4V nominal, so effectively 42 elements. Pretty nice margins. Indeed battery pack is where the tool companies make their profit with all of them being incompatible with each other, including Dewalt/Black and Decker (same company different brands) having just a small plastic notch to prevent interchange usage. -- Edit: durability depends on max charge and min/cut off discharge voltage (something like 4.13v/3.3 would be decent) - you can test those with voltmeter easily, temperature the batteries are run at, and discharge current. At around 400 cycles they should be at ~85% capacity.
    - xyzzy123 6y ago
      You can find x to y battery adapters on ebay, in case you found it as annoying as I did.
  - snovv_crash 6y ago

mdasen 6y ago

I think there's a combination of things here, but it's not the printer/razor model. You just don't have to replace the batteries frequently enough for that model. The battery pack should last for years. If you can cut your lawn in one charge and you cut it once a week, you should get around a decade out of it (assuming 500 charge cycles, LiIon batteries are usually 400-1,200 cycles). The battery you're looking at isn't just shrink-wrapped cells. I've seen 1-kWh e-bike batteries around $150 on AliExpress (shipped from China) that are just shrink-wrapped cells with a cable coming out where you're supposed to be knowledgable enough about batteries to make sure you use it safely and not catch on fire and such. This is in contrast to nicely packaged batteries that cost significantly more (like $800 for 1kWh at Luna Cycle). This battery is available when you want it (rather than shipped from China with a month wait), you're paying for the retail availability and service/support/returns, you're paying for knowing that the cells are likely reputable cells from a major manufacturer like Panasonic, LG, or Samsung, and you're maybe paying a little for the fact that it's a product-specific adaptation to fit the lawnmower. However, it doesn't look like they're marking you up much at all. E-bike batteries are a good comparison here. E-bike batteries are a relatively competitive market and the pricing sounds about right for something that's supported, has US distribution, decent quality, not a fire hazard, etc. - $350 for 420kWh. It doesn't really sound like you're getting over-charged. If you want a battery from a well-priced but reputable source, it's not $150 per kWh for batteries of this size. It sounds like they're charging you about what batteries of that size go for. You can certainly search around for ebike batteries and see that despite their being a competitive market there, you're not paying $150 per kWh. Doing a little searching, I can see 1 kWh for $800, 850 Wh for $620, 900 Wh for $600, etc. On Alibaba, I can see some cheaper things, but we're still talking $230 for 600 Wh, $400 for 900 Wh and who knows when they'll arrive or what quality they'll be. The lawn mower company might have a little margin on you, but they aren't over-charging a lot. From what I've seen for US-source e-bike batteries, it's pretty much in-line with my expectations. I've seen 420 Wh batteries a little cheaper (like $275 is the cheapest I've seen) which is cheaper, but you're looking at a slightly more niche product (a battery for a specific lawnmower) and likely looking at a bit more retail markup (like a big box store vs. a no-name online retailer), etc. $350 is pretty competitive and you're going to need to spend it once a decade so the possible $75 margin doesn't seem like much at $7.50 per year. I mean, you could maybe buy an e-bike battery and get it to work with the lawnmower, but I don't see e-bike batteries that are that much better for pricing. I mean, if you buy the lawnmower and it lasts you a decade and you love it, I don't feel like a $75 markup for a second decade on it feels like taking advantage of you. That just feels like retail markup and, frankly, I'd probably trust Luna Cycle more than the retailer I'd never heard of with the $275 420Wh battery. Luna's $460 650 Wh battery would cost the same as a $298 420 Wh battery, assuming the same price per Wh. $50 just doesn't seem bad.

asdff 6y ago

The problem is, ten years after you buy your mower and need to replace the original battery pack, will the manufacturer even make that proprietary shape? If owning an electric mower means buying an entirely new manufactured unit and battery every 10 years, delivered to your door in a shipping container across the pacific, that can't be much better for the environment than using a 25 year old $50 gas mower that's been circling the neighborhood craigslist forever. I just worry with the continual shedding of older technologies for better ones, that we fail to calculate the costs to replace these technologies and the costs to build new technologies as we get blinded by optimism and profit opportunities. The real rub on the environment more than anything else are our rampant consumerism and the globally extended supply lines needed to fuel that insatiable itch.

csours 6y ago
Well, there's the CO2 environment, and then there's my personal environment. In my personal environment, I don't want to use a gas mower due to extreme levels of particulate and un-burned gasoline pollution.
bluGill 6y ago
Most mowers have a 10 year planned obsolescence lifetime and will die before then. A 25 year old lawnmower probably cost a lot more for the engineering to make it last. Though even then they expect 3 years, but that is using it 40 hours a week so a homeowner doing an hour every Saturday is nothing even over 25 years.
- asdff 6y ago
  Any simple gas mower you buy off the line today can last practically forever if you just do basic maintenance and store it properly between seasons. They are just pretty simple engine designs that haven't really changed in decades. I used to be a groundskeeper, and as long as we kept the blades sharp and did basic engine maintenance like changing the oil and filter, we could just abuse a push mower all over the golf course for 50 hours a week summer after summer.
  - 6y ago

ip26 6y ago

The batteries are a lot cheaper when you buy them with a tool. I think they make the batteries by themselves expensive mainly to nudge you to buy another tool.

alister 6y ago

> a good battery mower may last a very long time However I’m worried about the availability of the mower’s battery 5-10 years from now. The battery packs have unique shapes, controllers, etc., which might be discontinued or become insanely expensive to replace in the future. If I were to buy a second mower battery as a backup, what would be the optimal strategy for maximizing the total life of my two batteries? Would it be best to: - never use the second battery until the first one dies - alternate between the two batteries - something else?

ProZsolt 6y ago
Batteries degrade while in storage and they degrade with every cycle. The best you can do is never store it fully charged. Never discharge it fully. Modern tools never let you do that, but if you store a "discharged" battery it will fully discharge(by self-discharge) over time. The best way is to charge it to 3.7V and then store it and check it at least yearly.