Author Topic: Electric Car Experiences  (Read 84735 times)

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Online tom66

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Re: Electric Car Experiences
« Reply #400 on: October 11, 2020, 10:31:44 am »
Not sure about Nissan's technology there.  I know Tesla have the capability to bring the car to a stop using the motor alone (on Model 3/Y using switched reluctance motors).  Just at the point where regen braking begins to fade (sub 3 mph) the drive unit switches to a stepper motor mode to bring the vehicle to a total stop with a small negative torque applied.

The auto-hold function on my car is pretty seamless so I don't see an urgent need for this kind of technology, but I suspect it could make the brake pads and components last longer if the motor is doing almost all the braking.
 

Offline bw2341

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Re: Electric Car Experiences
« Reply #401 on: October 14, 2020, 06:37:57 pm »
The most sensible control scheme for regenerative braking is the brake-by-wire brake pedal used on the Prius. I’m pretty sure that most hybrids and EVs use the same control scheme. Since the braking computer is constantly blending the regenerative and friction brakes, there should be no surprises when regenerative braking is unavailable.

The glaring exception is Tesla where regenerative braking is controlled with the accelerator pedal alone. It’s unsafe to train drivers to rarely use the brake pedal. It’s unsafe to have unpredictable braking force due to the condition of the battery. But since Tesla is the market leader, other EV makers are copying this control scheme. Hopefully, none of them are crazy enough to remove the Prius-style brake pedal.
 

Offline f4eru

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Re: Electric Car Experiences
« Reply #402 on: October 14, 2020, 09:40:48 pm »
hmm, nope. From 35 000km, I can say it's not unsafe at all. You use the mechanical brake at least 1-2 times a week, for different reasons, so the reflex really never goes  away.
Single pedal driving is really a good experience. it's the future. Or should I say, the present.

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #403 on: October 14, 2020, 10:08:05 pm »
hmm, nope. From 35 000km, I can say it's not unsafe at all. You use the mechanical brake at least 1-2 times a week, for different reasons, so the reflex really never goes  away.
Single pedal driving is really a good experience. it's the future. Or should I say, the present.

There will be drivers that prefer "free wheeling" gas pedals, and others that prefer it to provide engine braking (or its electrical equivalent).  Why not make it configurable?

It was configurable in 1960's Saabs...    the driver pulled a little lever, and it engaged or disengaged a freewheeling clutch...   unique feature, never seen it in any other car...  but very cool!

It is also configurable in my Ford hybrid.  Leave it in "Drive", and it freewheels.  Put it in "Low", and it slows when you let off the accelerator, simulating engine braking.

« Last Edit: October 14, 2020, 10:10:08 pm by SilverSolder »
 

Offline bw2341

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Re: Electric Car Experiences
« Reply #404 on: October 15, 2020, 12:11:19 am »
hmm, nope. From 35 000km, I can say it's not unsafe at all. You use the mechanical brake at least 1-2 times a week, for different reasons, so the reflex really never goes  away.
Single pedal driving is really a good experience. it's the future. Or should I say, the present.

Okay, "unsafe" might be a bit over the top. It is "less" safe in the same way as cruise control. One-pedal driving is a convenience feature that improves driver comfort. Still, I'm not happy about the unpredictable diminished regenerative braking response when the battery is full or too cold.

What really annoys me about Tesla's implementation is that they do not offer brake pedal control of regenerative braking at all. It does not take away from one-pedal driving to offer it as well.
« Last Edit: October 15, 2020, 12:13:49 am by bw2341 »
 

Online tom66

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Re: Electric Car Experiences
« Reply #405 on: October 15, 2020, 05:19:30 pm »
The glaring exception is Tesla where regenerative braking is controlled with the accelerator pedal alone. It’s unsafe to train drivers to rarely use the brake pedal. It’s unsafe to have unpredictable braking force due to the condition of the battery. But since Tesla is the market leader, other EV makers are copying this control scheme. Hopefully, none of them are crazy enough to remove the Prius-style brake pedal.

I disagree quite strongly.  In fact I think the default behaviour of a car should be to decelerate reasonably strongly if the accelerator is not applied.

For one, it encourages efficient driving and pacing and planning.  Pressing the brake pedal is "losing" the efficiency game, for at least some friction braking is applied.

Secondly, there are benefits in that the car is under more control from the driver, they can slow down immediately with just lifting off the accelerator, it's like always being in the engine braking region of a manual gearbox.  The 'coast-only' behaviour of many automatics is undesirable in this sense; drivers are alternating between the accel. and brake pedal all the time, which also leads to a sea of brake lights in traffic jams. Completely unnecessary.

Thirdly, there is a safety benefit.  Let's say you pass out while driving and your foot is now off the accelerator (most people can't keep pressure applied when they are unconscious.)  At least the car will come to a stop whereas many modern non-EVs will continue to creep or coast for a considerable amount of time. 

Finally, it will mean brake pads, discs and other components will last longer and fuel/electric economy should be improved. There are also benefits to reducing traffic jams as we get less 'snaking' from brake lights under even modest braking. 

I would say in case of regen being unavailable the car should emulate the same regen using the physical brakes,  it would be nice to see an indication of this on the dashboard e.g. the regen zone on the LCD turning white instead of green. 

Quote
There will be drivers that prefer "free wheeling" gas pedals, and others that prefer it to provide engine braking (or its electrical equivalent).  Why not make it configurable?

Many EVs and hybrids provide this with a "B" setting vs. a "D" setting.  Certainly the Prius, Leaf,  Golf GTE and e-Golf offer coast vs regen modes on the pedal.  The only thing that annoys me about this is on my car, it always starts in 'D' mode, but I've learned to press the gearstick down twice when I start driving to put it in 'B' mode.  I pretty much always drive in 'B' mode, only using 'D' occasionally on the motorway to improve efficiency.
« Last Edit: October 15, 2020, 05:22:58 pm by tom66 »
 

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #406 on: October 15, 2020, 05:32:41 pm »

Quote
There will be drivers that prefer "free wheeling" gas pedals, and others that prefer it to provide engine braking (or its electrical equivalent).  Why not make it configurable?

Many EVs and hybrids provide this with a "B" setting vs. a "D" setting.  Certainly the Prius, Leaf,  Golf GTE and e-Golf offer coast vs regen modes on the pedal.  The only thing that annoys me about this is on my car, it always starts in 'D' mode, but I've learned to press the gearstick down twice when I start driving to put it in 'B' mode.  I pretty much always drive in 'B' mode, only using 'D' occasionally on the motorway to improve efficiency.

Have you actually measured the difference in fuel economy?  All my attempts to measure showed a small advantage to the free-wheeling mode (combined with never using the brakes)!  :D
 

Online Gyro

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Re: Electric Car Experiences
« Reply #407 on: October 15, 2020, 08:51:31 pm »
It was configurable in 1960's Saabs...    the driver pulled a little lever, and it engaged or disengaged a freewheeling clutch...   unique feature, never seen it in any other car...  but very cool!

No, freewheel capability was integral to all cars fitted with optional overdrive units (extra selectable intermediate ratio epicyclic gear after the manual gearbox) back in those days - many Fords among others. They were made by Borg Warner, first developed in the 1930s and last used in a 1972 Ford model. They had a switch to enable the overdrive ratio and a mechanical lever to engage the unit (so that you could reverse!). I remember the one on my Dad's Ford Zodiac.
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Online tom66

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Re: Electric Car Experiences
« Reply #408 on: October 15, 2020, 09:19:49 pm »

Quote
There will be drivers that prefer "free wheeling" gas pedals, and others that prefer it to provide engine braking (or its electrical equivalent).  Why not make it configurable?

Many EVs and hybrids provide this with a "B" setting vs. a "D" setting.  Certainly the Prius, Leaf,  Golf GTE and e-Golf offer coast vs regen modes on the pedal.  The only thing that annoys me about this is on my car, it always starts in 'D' mode, but I've learned to press the gearstick down twice when I start driving to put it in 'B' mode.  I pretty much always drive in 'B' mode, only using 'D' occasionally on the motorway to improve efficiency.

Have you actually measured the difference in fuel economy?  All my attempts to measure showed a small advantage to the free-wheeling mode (combined with never using the brakes)!  :D

It's really down to physics.  If driving manually, and not using the cruise control, lifting off the pedal results in immediate braking which often isn't needed on the highway.   Regen braking is always less efficient than coasting if you do not need to decelerate as quickly as regen allows, because regen only recovers about ~50-70% of the kinetic energy. 

When using ACC, behaviour is very slightly modified - the car will coast for a bit longer before applying the physical brakes if it gets too close to a car, whereas in 'B' mode it will brake almost immediately. Also, if it is overspeed (e.g. you adjust the speed down for going into roadworks) it will brake using regen in 'B', whereas in the 'D' mode, it will coast and wait for the speed to reach the setpoint, which is more efficient if you can plan ahead!  I am surprised they went so far as to make this subtle modification, as it is not documented anywhere, but it is a nice distinction between the two modes.  I tend to use the 'B' mode with ACC on country roads where braking is more common due to traffic levels,  and 'D' mode on highways where braking is uncommon. 
« Last Edit: October 15, 2020, 09:21:24 pm by tom66 »
 

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #409 on: October 15, 2020, 09:26:41 pm »
It was configurable in 1960's Saabs...    the driver pulled a little lever, and it engaged or disengaged a freewheeling clutch...   unique feature, never seen it in any other car...  but very cool!

No, freewheel capability was integral to all cars fitted with optional overdrive units (extra selectable intermediate ratio epicyclic gear after the manual gearbox) back in those days - many Fords among others. They were made by Borg Warner, first developed in the 1930s and last used in a 1972 Ford model. They had a switch to enable the overdrive ratio and a mechanical lever to engage the unit (so that you could reverse!). I remember the one on my Dad's Ford Zodiac.

Saab had a special thing going on, with a freewheeling clutch.  I've had the pleasure of driving one, it is really rather unique. 

"An unusual feature of the Saab drivetrain was a 'freewheel' (overrunning clutch). This allowed the transmission to run faster than the engine, such as when decelerating, or descending a long hill." 
https://en.wikipedia.org/wiki/Saab_96

If I remember correctly, the 2 stroke models had it permanently enabled, but the V4 4-stroke models definitely had it configurable with a small T-shaped handle down by the floor...

You can hear it in use in this video clip:
« Last Edit: October 15, 2020, 09:36:32 pm by SilverSolder »
 

Online vk6zgo

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Re: Electric Car Experiences
« Reply #410 on: October 16, 2020, 01:07:13 am »
It was configurable in 1960's Saabs...    the driver pulled a little lever, and it engaged or disengaged a freewheeling clutch...   unique feature, never seen it in any other car...  but very cool!

No, freewheel capability was integral to all cars fitted with optional overdrive units (extra selectable intermediate ratio epicyclic gear after the manual gearbox) back in those days - many Fords among others. They were made by Borg Warner, first developed in the 1930s and last used in a 1972 Ford model. They had a switch to enable the overdrive ratio and a mechanical lever to engage the unit (so that you could reverse!). I remember the one on my Dad's Ford Zodiac.

Saab had a special thing going on, with a freewheeling clutch.  I've had the pleasure of driving one, it is really rather unique. 

"An unusual feature of the Saab drivetrain was a 'freewheel' (overrunning clutch). This allowed the transmission to run faster than the engine, such as when decelerating, or descending a long hill." 
https://en.wikipedia.org/wiki/Saab_96

If I remember correctly, the 2 stroke models had it permanently enabled, but the V4 4-stroke models definitely had it configurable with a small T-shaped handle down by the floor...

You can hear it in use in this video clip:


Such devices were "all the go" in the 1930s, but they were mostly ditched for conventional systems, due to poor reliability & concern about lack of "engine braking".

That decade was one of great automotive innovation, much of which came to nothing.

One of the 1930s Singer cars had a transmission you could use in no fewer than three modes,------ as a conventional manual, a manual with automatic clutch, & a preselector.

It also had "Startex" ignition--------if your engine stalled, it would automatically re-start.

All this, without a microprocesser in sight! (unless you were a time traveller).
 

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #411 on: October 16, 2020, 01:35:49 am »
[...]

Such devices were "all the go" in the 1930s, but they were mostly ditched for conventional systems, due to poor reliability & concern about lack of "engine braking".

That decade was one of great automotive innovation, much of which came to nothing.

One of the 1930s Singer cars had a transmission you could use in no fewer than three modes,------ as a conventional manual, a manual with automatic clutch, & a preselector.

It also had "Startex" ignition--------if your engine stalled, it would automatically re-start.

All this, without a microprocesser in sight! (unless you were a time traveller).

The Saab freewheeling system was put in specifically to avoid drivers using the 2-stroke engine for engine braking, which could starve it of lubrication and caused excessive wear.  Being a Saab, their system was obviously well engineered and generally reliable.  The funny thing is, when they moved on to 4-stroke engines in the later part of the 60's, they kept the free wheeling feature...  most likely because Saab drivers were used to it being there and would have considered it a retrograde step to remove it!

It is funny to study vintage cars and see all the crazy things they were trying to do back in the day.  In the early motoring epoch, there was much more variety.  Nowadays, cars have converged to a standard formula - accelerator, brake, and clutch always in the same order, most controls are similar, transmissions are very samey, etc.   

The convergence was probably mostly complete already by the 70's?
 

Offline DougSpindler

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Re: Electric Car Experiences
« Reply #412 on: October 17, 2020, 05:14:47 am »
Ah the good old days of gross polluting winning would of a 2-stroke engine.  I think there’s a reason we moved on from that technology.
 

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #413 on: October 17, 2020, 03:16:06 pm »
Ah the good old days of gross polluting winning would of a 2-stroke engine.  I think there’s a reason we moved on from that technology.

Yep, but you can't beat the sound effects!  :D

Two strokes are still used in some applications - chain saws, leaf blowers, strimmers, etc. - it's going to be hard to dislodge them from that last stronghold, nothing beats their power-to-weight ratio!
 

Offline f4eru

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Re: Electric Car Experiences
« Reply #414 on: October 19, 2020, 12:00:52 pm »
can you please come back to topic ?

Online nctnico

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Re: Electric Car Experiences
« Reply #415 on: October 19, 2020, 10:20:28 pm »
Ah the good old days of gross polluting winning would of a 2-stroke engine.  I think there’s a reason we moved on from that technology.

Yep, but you can't beat the sound effects!  :D

Two strokes are still used in some applications - chain saws, leaf blowers, strimmers, etc. - it's going to be hard to dislodge them from that last stronghold, nothing beats their power-to-weight ratio!
Larger diesel engines (as found on ships) are also 2 stroke. But yes, chains saws and strimmer should be electrified. Leaf blowers are the worst invention ever. What about the good old broom?
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Offline DougSpindler

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Re: Electric Car Experiences
« Reply #416 on: October 20, 2020, 01:53:51 am »
Electric chain saws work very well until you accidentally cut the power cord.  I have one for use around my property.  Prefer it over the gas one.  Electric and battery chain saws will never replace electric.  I can’t see someone 100 feet up a tree with a 100 foot extension cord.  Or your 100 feet up a tree when the battery on your chain saw dies.   Other issue with electric chain saws is I just can’t seem to find an outlet in the wooded part of my property.

Issue with a broom is the just don’t work as well or as quickly as a leaf blower.  I have an electric leaf blower and in 5 minutes I can clean an area that would take 45 minutes to sweep.  While I’m not a fan of the noisy gas powered ones, I do understand there usefulness. 
 

Offline coppice

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Re: Electric Car Experiences
« Reply #417 on: October 20, 2020, 01:35:51 pm »
Electric chain saws work very well until you accidentally cut the power cord.  I have one for use around my property.  Prefer it over the gas one.  Electric and battery chain saws will never replace electric.  I can’t see someone 100 feet up a tree with a 100 foot extension cord.  Or your 100 feet up a tree when the battery on your chain saw dies.   Other issue with electric chain saws is I just can’t seem to find an outlet in the wooded part of my property.

Issue with a broom is the just don’t work as well or as quickly as a leaf blower.  I have an electric leaf blower and in 5 minutes I can clean an area that would take 45 minutes to sweep.  While I’m not a fan of the noisy gas powered ones, I do understand there usefulness.
There are some really excellent battery powered garden tools these days, although the good ones aren't cheap. I used a battery powered hedge trimmer some time ago, that was pretty hopeless when it met a thick branch. Recently I used my neighbour's new Stihl battery powered hedge trimmers to trim some shared hedging. They just keep going when they encounter a really thick branch, just like a gas or mains powered one would. The battery seems to last a long time, too. I was trimming for about 40 or 50 minutes, without flattening the battery. I was very impressed by everything except the price. :)
 

Offline DougSpindler

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Re: Electric Car Experiences
« Reply #418 on: October 20, 2020, 02:18:31 pm »
Electric chain saws work very well until you accidentally cut the power cord.  I have one for use around my property.  Prefer it over the gas one.  Electric and battery chain saws will never replace electric.  I can’t see someone 100 feet up a tree with a 100 foot extension cord.  Or your 100 feet up a tree when the battery on your chain saw dies.   Other issue with electric chain saws is I just can’t seem to find an outlet in the wooded part of my property.

Issue with a broom is the just don’t work as well or as quickly as a leaf blower.  I have an electric leaf blower and in 5 minutes I can clean an area that would take 45 minutes to sweep.  While I’m not a fan of the noisy gas powered ones, I do understand there usefulness.
There are some really excellent battery powered garden tools these days, although the good ones aren't cheap. I used a battery powered hedge trimmer some time ago, that was pretty hopeless when it met a thick branch. Recently I used my neighbour's new Stihl battery powered hedge trimmers to trim some shared hedging. They just keep going when they encounter a really thick branch, just like a gas or mains powered one would. The battery seems to last a long time, too. I was trimming for about 40 or 50 minutes, without flattening the battery. I was very impressed by everything except the price. :)

I agree with you completely.  But there’s a difference between home owners cutting tree branches/hedges ever so often vs. someone who does it for 8 hour every day.  I can’t see someone who cuts trees professionally using a battery chainsaw.
 

Offline ahbushnell

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Re: Electric Car Experiences
« Reply #419 on: October 20, 2020, 05:04:26 pm »
Electric chain saws work very well until you accidentally cut the power cord.  I have one for use around my property.  Prefer it over the gas one.  Electric and battery chain saws will never replace electric.  I can’t see someone 100 feet up a tree with a 100 foot extension cord.  Or your 100 feet up a tree when the battery on your chain saw dies.   Other issue with electric chain saws is I just can’t seem to find an outlet in the wooded part of my property.

Issue with a broom is the just don’t work as well or as quickly as a leaf blower.  I have an electric leaf blower and in 5 minutes I can clean an area that would take 45 minutes to sweep.  While I’m not a fan of the noisy gas powered ones, I do understand there usefulness.
New invention.  Battery powered leaf blower. 
 

Offline SilverSolder

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Re: Electric Car Experiences
« Reply #420 on: October 20, 2020, 05:50:25 pm »
Ah the good old days of gross polluting winning would of a 2-stroke engine.  I think there’s a reason we moved on from that technology.

Yep, but you can't beat the sound effects!  :D

Two strokes are still used in some applications - chain saws, leaf blowers, strimmers, etc. - it's going to be hard to dislodge them from that last stronghold, nothing beats their power-to-weight ratio!
Larger diesel engines (as found on ships) are also 2 stroke. But yes, chains saws and strimmer should be electrified. Leaf blowers are the worst invention ever. What about the good old broom?

A broom?  -  ...it already takes me two hours to clear the leaves on a bad day - using 2 different leaf blowers, one of them a 5hp 4 stroke on wheels, the other a 2 stroke hand-held.  It would take a whole weekend to do that with a broom, if not more! 

I have to fill the fuel tank twice on the handheld to finish the job...  Electric versions of these tools are not really viable once the size of the job gets to a certain level, with unrealistically long and heavy gauge extension cords, or short-lived batteries.

I would love a fusion powered electric version though, to do the whole thing in 5 minutes!  :D

 

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Re: Electric Car Experiences
« Reply #421 on: October 20, 2020, 07:51:29 pm »
But there’s a difference between home owners cutting tree branches/hedges ever so often vs. someone who does it for 8 hour every day.  I can’t see someone who cuts trees professionally using a battery chainsaw.
Certainly not for clear felling or skid duties but the tree climbing arborists are embracing battery powered saws.

New brushless motors with their lightweight and efficiencies are opening up a whole list of new use cases.

No air filters, no fuel filters, no recoil starter, fuel and/or contamination issues, spark ignition/plug problems and low noise.
What's not to like ?
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Offline SilverSolder

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Re: Electric Car Experiences
« Reply #422 on: October 21, 2020, 03:10:24 pm »
But there’s a difference between home owners cutting tree branches/hedges ever so often vs. someone who does it for 8 hour every day.  I can’t see someone who cuts trees professionally using a battery chainsaw.
Certainly not for clear felling or skid duties but the tree climbing arborists are embracing battery powered saws.

New brushless motors with their lightweight and efficiencies are opening up a whole list of new use cases.

No air filters, no fuel filters, no recoil starter, fuel and/or contamination issues, spark ignition/plug problems and low noise.
What's not to like ?

Apart from having to keep them charged, battery aging is the worst problem, in my experience.  All my battery powered electric tools have died from that cause, and they had a long drawn out period of low performance before dying completely.  The replacement batteries are so expensive that they are just not worth it, just another assault on your wallet by some cheesy MBA.

So, I have gone back to "old school" corded equipment for all electric tools.  They generally last decades and are always "charged".  -  For the garden, I live with the fact that petrol engines have to be maintained occasionally - and in fairness, it is pretty rare that any of my 5 ICE powered outdoor tools misbehave. What works for me is to always add fuel stabilizer to the jerry can when buying fresh petrol - that stuff really works, I never encounter gummed carbs etc. any more, unlike the "bad old days".

 

Offline DougSpindler

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Re: Electric Car Experiences
« Reply #423 on: October 22, 2020, 04:00:44 am »
That’s the issue with battery powered tools.
 


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