\"4 Die in Fire Caused by Batteries in E-Bike Shop Near Chinatown\"...

[Eddy Lee]

On Wednesday, June 21, 2023 at 6:03:29 PM UTC-7, Don Y wrote:

On 6/21/2023 4:40 PM, Eddy Lee wrote:
On Wednesday, June 21, 2023 at 4:31:54 PM UTC-7, Don Y wrote:
On 6/21/2023 4:14 PM, Eddy Lee wrote:
On Wednesday, June 21, 2023 at 3:53:35 PM UTC-7, Don Y wrote:
On 6/21/2023 3:48 PM, Eddy Lee wrote:
On Wednesday, June 21, 2023 at 3:39:55 PM UTC-7, Don Y wrote:
On 6/21/2023 3:38 PM, Don Y wrote:
Finally, wheelchairs have been designed/serviced with
lead acid batteries since... forever. So, changing the
battery chemistry means you are doing something that the
manufacturer hasn\'t endorsed, NOR TESTED (for safety).

Sell the chair -- or, die (unexpectedly?) and have someone
else assume ownership -- and what will they expect from
\"your\" chair? Have you printed a disclaimer on it and/or
suitably modified the wiring and CHARGE CONNECTOR to make
it incredibly obvious that this is no longer an industry
standard (approved!) design? Or, will the new owner just
assume that the charger that accompanied it was designed
to the same standards as those on all other chairs?

[Ignore the moral obligation -- esp if you\'re already dead!]

I.e., electric scooters, cell phones, laptops, EVs, etc.
have firms with lots of staff (and lawyers) to ensure the
safety of the item being sold.

YET STILL MANAGE TO HAVE THESE SORTS OF EVENTS OCCUR!
Ask yourself how YOU will address these issues with YOUR
(modified) vehicle...

My batteries are protected from over-voltage and under-voltage, and manually rebalanced/replaced after several cycles. I monitor the temperature and/or smoke signal.
You didn\'t answer my question.

When you opt to sell your vehicle, how will you expect a buyer
to deal with your \"modifications\"? Will you assert that the
car is JUST AS SAFE/reliable as when the dealer produced it?

I don\'t plan on selling it. It\'s worth around $3K to $4K. I would run it down to the ground.
PRETEND it was actually worth something...

I mean if I have to buy another 2012 Leaf with 5 to 6 bars. I have seen some at low as 3 bars. I am just trying to hold on as long as possible.

The vehicle ECU doesn\'t know about the expansion batteries when estimating bars.
And your magic switches? \"Pay no attention to that man behind the curtain....\"

You\'ve made changes to the power source in the vehicle. It\'s not
as easily dismissed as installing a new stereo or air freshener.

The battery BMS estimates capacity internal to the module. So, my external connections are not accounted for. Due to different chemicals, my external batteries have lower operating voltage. As a result, I tend to get extended range when the main is near empty. More power/current is drawn from expansion batteries at the low end.

If the guy who put the jet engine in a VW bug opts to sell his
contraption, it is pretty damn obvious to a buyer that you\'re
not getting a \"stock\" VW bug.

Yes, i have no intention of selling. If time come, i might just move my custom mods to another vehicle. I might even move to a Bolt, since GM is no longer replacing them. I think a depleted (lower capacity/SOH) Bolt might be less prone to fire.

Would someone buying your vehicle realize the extent of the modifications,
their possible consequences, and be able to gauge the risks he takes on
with the purchase?

I can easily remove all mods if necessary, if there is a need to sell.

I can put lithium batteries in my chair and still continue to use
it in reasonable safety -- by being prudent in *how* I use it,
how I charge it, etc.

Same for me on my EV. And I check cell balance often. Higher cap cell is just as bad as lower cap, since high cap cell often cause low cap cell somewhere else.

But, being able to hide all of those issues in the same \"turnkey\"
manner that the chair manufacturer does is simply not practical;
why take on those tasks if *I* am the intended operator?

(i.e., like YOU being the intended operator of your vehicle)

The problem comes when the item leaves your possession/control
(i.e., you drop dead, tomorrow; someone looking at your estate
sees \"one electric vehicle\". THEY don\'t see a *modified* electric
vehicle any more than someone looking at my chair would see
a *modified* chair)

I\'ll have proper dismantling manual in the car in that case.

[This is particularly true as chairs tend to be designed for
each particular occupant]

If the manufacturer hasn\'t seen fit to accommodate different
battery chemistries (or, capacities) with more advanced charge
control, why would I want to do so if I can achieve the same
results with diligence? *I* know my charge/discharge practices
so why should the chair have to accommodate an unconstrained set
of such practices?

A wheelchair is the PERFECT application for active load/charge
management as the controls are ALWAYS connected to the battery,
the battery is not removable, the chair is not operable with the
battery removed (OR while being charged, for obvious reasons!).

Why does it have a silly \"gas gauge\" display? It\'s not like
a car where you can refuel (or, get a tow) if you happen to
run out of power some distance from YOUR charger (because the
charger isn\'t part of the chair and you don\'t carry it along
with you in your travels; and, can\'t just pull into a
\"wheelchair charging station\")

Why can\'t it look at power consumption WITH THIS LOAD IN THIS
TERRAIN and estimate remaining miles/time left in the pack? Or,
assume I will return to my staring point by backtracing my current
route (so, guesstimate what that load would likely be). It\'s
not like there are going to be 5 different occupants varying
from day-to-day and hour-to-hour.

Why can\'t it tell me that a cell is (likely) shorted? With practice,
I can come to that conclusion by noting where the charger tops out.

Or, the state of health of the battery pack (you saw it yesterday;
and the day before; and all the way back to the day it was INSTALLED!)?
And predict when it is in need of replacement?

Yet, no one does these things (at least when my chair was designed).

Part of this is inertia. And, more is related to the nature of
the consumers -- you are likely dependant on <someone> to keep
your chair running so let THEM make \"value judgements\":
\"Ah, you\'re finding that you don\'t have enough range? We can
upgrade you to THE larger battery class...\"

All these things could and should be done for your chair, if your chair is really $40K, 10x more than my EV. Lithium batteries need to be monitored/protected very carefully.

 

[Don Y]

On 6/21/2023 6:45 PM, Eddy Lee wrote:

Would someone buying your vehicle realize the extent of the
modifications, their possible consequences, and be able to gauge the risks
he takes on with the purchase?

I can easily remove all mods if necessary, if there is a need to sell.

IF YOU ARE ALIVE TO DO SO!

SWMBO has directions as to how my various bits of kit are to be
disposed of, if I drop dead tomorrow. What if she has forgotten
this \"duty\"?

But, what if she drops dead before me? Do I line up someone else
to take on that role?

What if we both die together?

We\'ve instructions to our individual estate executors but thinking
that they will understand anything beyond \"DESTROY x, y and z\"
(no, not DISCARD!) is wishful thinking.

I.e., the modified items exist regardless of our INTENTIONS with
respect to their disposition. You can\'t make them safe. Unless
you can do so NOW.

I can put lithium batteries in my chair and still continue to use it in
reasonable safety -- by being prudent in *how* I use it, how I charge it,
etc.

Same for me on my EV. And I check cell balance often. Higher cap cell is
just as bad as lower cap, since high cap cell often cause low cap cell
somewhere else.

Again, what happens when you no longer are doing that -- or, are
no longer around to TELL someone to do those things?

A jet-powered VW bug stands out as being different. A modified
EV or EW (Electric Wheelchair) doesn\'t.

[This is particularly true as chairs tend to be designed for each
particular occupant]

If the manufacturer hasn\'t seen fit to accommodate different battery
chemistries (or, capacities) with more advanced charge control, why would
I want to do so if I can achieve the same results with diligence? *I* know
my charge/discharge practices so why should the chair have to accommodate
an unconstrained set of such practices?

A wheelchair is the PERFECT application for active load/charge management
as the controls are ALWAYS connected to the battery, the battery is not
removable, the chair is not operable with the battery removed (OR while
being charged, for obvious reasons!).

Why does it have a silly \"gas gauge\" display? It\'s not like a car where
you can refuel (or, get a tow) if you happen to run out of power some
distance from YOUR charger (because the charger isn\'t part of the chair
and you don\'t carry it along with you in your travels; and, can\'t just
pull into a \"wheelchair charging station\")

Why can\'t it look at power consumption WITH THIS LOAD IN THIS TERRAIN and
estimate remaining miles/time left in the pack? Or, assume I will return
to my staring point by backtracing my current route (so, guesstimate what
that load would likely be). It\'s not like there are going to be 5
different occupants varying from day-to-day and hour-to-hour.

Why can\'t it tell me that a cell is (likely) shorted? With practice, I can
come to that conclusion by noting where the charger tops out.

Or, the state of health of the battery pack (you saw it yesterday; and the
day before; and all the way back to the day it was INSTALLED!)? And
predict when it is in need of replacement?

Yet, no one does these things (at least when my chair was designed).

Part of this is inertia. And, more is related to the nature of the
consumers -- you are likely dependant on <someone> to keep your chair
running so let THEM make \"value judgements\": \"Ah, you\'re finding that you
don\'t have enough range? We can upgrade you to THE larger battery
class...\"

All these things could and should be done for your chair, if your chair is
really $40K, 10x more than my EV.

Why? If I can operate the chair knowing roughly how much travel
I can get out of a charge, why should I invest the time to design
a system to give me a better estimate? I\'m not in the wheelchair
business (and, I only use it infrequently).

Lithium batteries need to be
monitored/protected very carefully.

But I don\'t have to put those provisions INTO the chair\'s design.
Unlike an EV, I can remove the battery relatively easily (esp if
my reason for moving to lithium was to reduce the weight of the
chair).

LOOKING at the chair, how would you know that the power source
had been changed (the batteries are in a covered compartment
UNDER the seat; a chair without the elevator function would
be difficult to even examine those!)

 

[Eddy Lee]

On Wednesday, June 21, 2023 at 7:03:49 PM UTC-7, Don Y wrote:

On 6/21/2023 6:45 PM, Eddy Lee wrote:
Would someone buying your vehicle realize the extent of the
modifications, their possible consequences, and be able to gauge the risks
he takes on with the purchase?

I can easily remove all mods if necessary, if there is a need to sell.
IF YOU ARE ALIVE TO DO SO!

I\'ll post battery disassembly instructions inside the vehicle.

 

[Eddy Lee]

On Wednesday, June 21, 2023 at 7:12:02 PM UTC-7, Eddy Lee wrote:

On Wednesday, June 21, 2023 at 7:03:49 PM UTC-7, Don Y wrote:
On 6/21/2023 6:45 PM, Eddy Lee wrote:
Would someone buying your vehicle realize the extent of the
modifications, their possible consequences, and be able to gauge the risks
he takes on with the purchase?

I can easily remove all mods if necessary, if there is a need to sell..
IF YOU ARE ALIVE TO DO SO!
I\'ll post battery disassembly instructions inside the vehicle.

The batteries are all connected with
quick-connect spade/coaxial connectors.
No tool needed, just pull them apart.
Wear 400V high voltage glove if necessary.

Remove in order:
1. 100A fuse from center of #1
2. Coaxial connector on rear end of #1.
3. 30A main feed circuit breaker from #1.
4. Main wire feed from #1.
5. 10A breaker from center of #2
6. Tapping wires from #2
7. Tapping wires between #2 and #3
8. 10A breaker from center of #3

Voltage after stage
1. 192V 192V 384V 384V
5. 192V 192V 192V 192V 384V
8. 192V 192V 192V 192V 192V 192V

PS: will post pictures and location maps.

 

[John Larkin]

On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
<bloggs.fredbloggs.fred@gmail.com> wrote:

On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.

And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

 

[Eddy Lee]

On Thursday, June 22, 2023 at 7:06:39 AM UTC-7, John Larkin wrote:

On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.


It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

When one is shorted, it will take out the inline fuse or wire. This will cause the module to be under-cap and the rest to be over-cap (and thus module voltage mismatch).

Very important to check and balance cells often, before it\'s too late. Need periodic battery tune-up.

 

[ke...@kjwdesigns.com]

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:

On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.

In the Tesla Model 3 groups of 46 cells are in parallel.

https://www.marklines.com/en/report/rep1830_201903

kw

 

[Anthony William Sloman]

On Friday, June 23, 2023 at 12:06:39 AM UTC+10, John Larkin wrote:

On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

Battery packs built in quality megafactories have internal and surface temperature sensors. The failure mode that John Larkin is talking about is a gradual process - if the cells get too hot for too long, their self-discharge rate rises, which means that the core of the battery gets hot - and hotter than the surface - which the temperature sensors can detect.

As the battery gets hotter, the self discharge rate rises and there is a temperature where the self-discharge process can run away.

A properly monitored battery pack can give you a lot of early warning when this state is being approached, and you can dump the battery in a safe place long before it\'s likely to catch fire. There\'s no fool-proof way of preventing an ingenious fool from ignoring the warnings, any more than you can stop a gun nut from having accessible guns around their house, but it is a potentially manageable risk.

--
Bil Sloman, Sydney

 

[John Larkin]

On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
<keith@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.

Once the cell has ignited internally, it\'s too late. The entire pack
will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.

 

[Anthony William Sloman]

On Friday, June 23, 2023 at 1:02:48 AM UTC+10, John Larkin wrote:

On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.

Once the cell has ignited internally, it\'s too late. The entire pack will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.

This is saying that there\'s no point in locking the stable door after the horse has bolted.

If you monitor the internal temperature of the battery pack (as well as it\'s surface temperature) you can detect self-heating long before any of the cells can get hot enough to go into thermal run-away.

Flyguy has the same problem. He can\'t imagine that you could detect a problem with a battery early enough to stop it from progressing to the point of thermal runaway and a fire. He seen to suffer from senile dementia. One has to wonder what John Larkin\'s problem is.

--
Bill Sloman, Sydney

 

[ke...@kjwdesigns.com]

On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:

On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.
Once the cell has ignited internally, it\'s too late. The entire pack
will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.

\"Once the cell has ignited internally, it\'s too late. The entire pack will burn.\"

That is not true - one cell igniting internal MAY cause the entire pack to burn but the amount of energy in an individual cell in a car such as a Tesla Model 3 is only 10-15Wh of energy and that is inside a steel casing for each cell. There is also some additional combustion energy in the electrolyte and electrodes if they reach critical temperatures.

There is much design and testing done such that except under exceptional circumstances any thermal event is contained within the steel envelope of the individual cell.

Such tests as gross overcharging and penetration of the battery pack by external objects are performed. One facility I know of has test chambers rated for explosion and fire to perform such tests safely.

kw

 

[ke...@kjwdesigns.com]

On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:

On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.
Once the cell has ignited internally, it\'s too late. The entire pack
will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.

\"Teslas do explode while parked\"

They don\'t explode.

Some have caught fire.

Conventional vehicles also catch fire unattended as well.

GM has recalled millions of conventional cars and trucks because of fire risk.

They even told owners to park cars outside until they had repairs performed..

kw

 

[ke...@kjwdesigns.com]

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
....

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.
....

Most manufacturers other than Tesla use larger format cells than 18650/2170 etc.

Even those larger cells have features that allow individual regions within the cell to become isolated in the event of a dendrite causing the two electrodes to be connected - usually the dendrite itself will self-destruct and be self-healing in a similar way to film capacitors subjected to overvoltage. There is just slight loss of capacity.

Again, each cell is within a steel enclosure that serves to contain the majority of thermal events. Accurate battery management and good quality control in manufacture minimize the chances of the thermal event in the first place.

kw

 

[Flyguy]

On Thursday, June 22, 2023 at 10:56:50 AM UTC-7, ke...@kjwdesigns.com wrote:

On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:
On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required....

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.
Once the cell has ignited internally, it\'s too late. The entire pack
will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.
\"Teslas do explode while parked\"

They don\'t explode.

Some have caught fire.

Conventional vehicles also catch fire unattended as well.

GM has recalled millions of conventional cars and trucks because of fire risk.

They even told owners to park cars outside until they had repairs performed.

kw

Yes, Teslas CAN EXPLODE:
https://www.youtube.com/watch?v=AmbHpqWjMVE
When you have very rapid heat generated inside of a sealed container you get an explosion. Why do you think water heaters have a pressure relief valve?

 

[Anthony William Sloman]

On Friday, September 1, 2023 at 3:33:56 PM UTC+10, Flyguy wrote:

On Thursday, June 22, 2023 at 10:56:50 AM UTC-7, ke...@kjwdesigns..com wrote:
On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:
On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\" <ke....@kjwdesigns.com> wrote:
On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs <bloggs.fred....@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y <blocked...@foo.invalid> wrote:

<snip>

Yes, Teslas CAN EXPLODE:
https://www.youtube.com/watch?v=AmbHpqWjMVE
When you have very rapid heat generated inside of a sealed container you get an explosion. Why do you think water heaters have a pressure relief valve?

The Tesla control system is designed to prevent this from happening,]

https://bestsellingcarsblog.com/2023/04/media-post-what-is-teslas-thermal-management-system-and-how-does-it-work/

That battery temperature is monitored, and there are systems in place to cool it off if it get too hot - way short of explosion.

It\'s possible that an idiot owner with Sewage Sweeper\'s level of misplaced self-confidence could get the car into a state where it might get close to thermal runaway, but the system should be designed to cope with them and other natural hazards.

No design is prefect, but Sewage Sweeper has a very strange idea of how batteries behave when they are getting close to thermal runaway. He seems to think that they could look perfectly normal and measure out as being barely warmer than their environment, then suddenly heat up to the point of bursting. It doesn\'t work that way. Self-discharge gets worse as the battery gets older, and warms the battery above ambient (which makes it worse), but it does have to get remarkably warm for thermal runaway to set in. Any kind of battery monitoring system will have loads of early warning of this kind of situation and will be insisting that the driver takes the car straight to the nearest service centre long before they could catch on fire.

--
Bill Sloman, Sydney

 

[whit3rd]

On Wednesday, June 21, 2023 at 2:34:11 PM UTC-7, ke...@kjwdesigns.com wrote:

On Wednesday, 21 June 2023 at 08:08:55 UTC-7, John Larkin wrote:

We walked past a garden yesterday that had a pile of the little
solar-charged-LED light things ready to be disposed of. The cheap
batteries die in a year or two.
They are usually NiMH batteries in those cheap solar garden lights, not Li-Ion

They get run to depletion every night which is a hard life for them.

Yeah, but a lot of \'em are just AAAs loaded into spring clips; either replace the
battery, OR just put in an alkaline or \'heavy duty\' battery for the evening.... batteries
dead was a problem with lead-acid solar-charged lights, too.

 

[John Larkin]

On Thu, 31 Aug 2023 22:33:51 -0700 (PDT), Flyguy
<soar2morrow@yahoo.com> wrote:

On Thursday, June 22, 2023 at 10:56:50?AM UTC-7, ke...@kjwdesigns.com wrote:
On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:
On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\"
ke...@kjwdesigns.com> wrote:

On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs
bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y
blocked...@foo.invalid> wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)
https://dnyuz.com/2023/06/21/how-e-bike-battery-fires-became-a-deadly-crisis-in-new-york-city/

Those batteries have everything going against them: shock and vibration, exposure to the elements, exposure to airborne corrosives in city air, people experimenting with chargers- maybe not even intended for lithium, abuse from deep discharge with people running them until their e-bike goes dead.
And being cheap no-name stuff to start.

It occurs to me that even gigantic lithium batteries are made from a
lot of small cells. One cell shorting will ignite the entire pack. So
the bigger the battery (Tesla semi?) the higher the probability of a
fire and, of course, the bigger the fire.

Vehicle betteries are of course exposed to hazards that stationary,
like utility backup, ones aren\'t, but even the stationary batteries
built in quality megafactories catch fire.

With Tesla batteries every individual cell has a fusible link that would rupture isolated the cell from the rest in that rare occurrence.
Once the cell has ignited internally, it\'s too late. The entire pack
will burn. Teslas do explode while parked. Cheap batteries are worse.
A truck will be worse.
\"Teslas do explode while parked\"

They don\'t explode.

Some have caught fire.

Conventional vehicles also catch fire unattended as well.

GM has recalled millions of conventional cars and trucks because of fire risk.

They even told owners to park cars outside until they had repairs performed.

kw

Yes, Teslas CAN EXPLODE:
https://www.youtube.com/watch?v=AmbHpqWjMVE
When you have very rapid heat generated inside of a sealed container you get an explosion. Why do you think water heaters have a pressure relief valve?

It doesn\'t look like there will be much left to investigate.

 

[Flyguy]

On Thursday, August 31, 2023 at 11:00:34 PM UTC-7, Anthony William Sloman wrote:

On Friday, September 1, 2023 at 3:33:56 PM UTC+10, Flyguy wrote:
On Thursday, June 22, 2023 at 10:56:50 AM UTC-7, ke...@kjwdesigns.com wrote:
On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:
On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\" <ke...@kjwdesigns.com> wrote:
On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs <bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y <blocked...@foo.invalid> wrote:
snip
Yes, Teslas CAN EXPLODE:
https://www.youtube.com/watch?v=AmbHpqWjMVE
When you have very rapid heat generated inside of a sealed container you get an explosion. Why do you think water heaters have a pressure relief valve?
The Tesla control system is designed to prevent this from happening,]

Hey Bozo, you apparently didn\'t watch the video.

https://bestsellingcarsblog.com/2023/04/media-post-what-is-teslas-thermal-management-system-and-how-does-it-work/

That battery temperature is monitored, and there are systems in place to cool it off if it get too hot - way short of explosion.

It\'s possible that an idiot owner with Sewage Sweeper\'s level of misplaced self-confidence could get the car into a state where it might get close to thermal runaway, but the system should be designed to cope with them and other natural hazards.

No design is prefect, but Sewage Sweeper has a very strange idea of how batteries behave when they are getting close to thermal runaway. He seems to think that they could look perfectly normal and measure out as being barely warmer than their environment, then suddenly heat up to the point of bursting. It doesn\'t work that way. Self-discharge gets worse as the battery gets older, and warms the battery above ambient (which makes it worse), but it does have to get remarkably warm for thermal runaway to set in. Any kind of battery monitoring system will have loads of early warning of this kind of situation and will be insisting that the driver takes the car straight to the nearest service centre long before they could catch on fire.

LOL! You are just FUCKING CLUELESS, Bozo! Did that Tesla \"warn\" the driver to take it to a service CENTER??? Maybe it sent him a text before it EXPLODED!

--
Bozo Bill Slowman, Sydney

Bozo\'s Sewage Sweeper

 

[gggg gggg]

On Tuesday, June 20, 2023 at 3:51:58 PM UTC-7, Don Y wrote:

I guess that gives me second thoughts about replacing the lead-acid
batteries in my wheelchair with lithium given the size required...

(Not going to store a $40K chair outside \"just to be safe\"!)

The following on China may be of interest:

https://www.youtube.com/watch?v=zS6dwGFv5HI&t=23s

 

[Anthony William Sloman]

On Tuesday, September 5, 2023 at 1:51:14 PM UTC+10, Flyguy wrote:

On Thursday, August 31, 2023 at 11:00:34 PM UTC-7, Anthony William Sloman wrote:
On Friday, September 1, 2023 at 3:33:56 PM UTC+10, Flyguy wrote:
On Thursday, June 22, 2023 at 10:56:50 AM UTC-7, ke...@kjwdesigns.com wrote:
On Thursday, 22 June 2023 at 08:02:48 UTC-7, John Larkin wrote:
On Thu, 22 Jun 2023 07:35:21 -0700 (PDT), \"ke...@kjwdesigns.com\" <ke...@kjwdesigns.com> wrote:
On Thursday, 22 June 2023 at 07:06:39 UTC-7, John Larkin wrote:
On Wed, 21 Jun 2023 13:31:34 -0700 (PDT), Fred Bloggs <bloggs.fred...@gmail.com> wrote:
On Wednesday, June 21, 2023 at 3:43:57?PM UTC-4, John Larkin wrote:
On Tue, 20 Jun 2023 15:51:45 -0700, Don Y <blocked...@foo.invalid> wrote:

<snip>

Yes, Teslas CAN EXPLODE:
https://www.youtube.com/watch?v=AmbHpqWjMVE
When you have very rapid heat generated inside of a sealed container you get an explosion. Why do you think water heaters have a pressure relief valve?
The Tesla control system is designed to prevent this from happening,

Hey Bozo, you apparently didn\'t watch the video.

Why would I bother. You don\'t understand the links you post.

https://bestsellingcarsblog.com/2023/04/media-post-what-is-teslas-thermal-management-system-and-how-does-it-work/

That battery temperature is monitored, and there are systems in place to cool it off if it get too hot - way short of explosion.

It\'s possible that an idiot owner with Sewage Sweeper\'s level of misplaced self-confidence could get the car into a state where it might get close to thermal runaway, but the system should be designed to cope with them and other natural hazards.

No design is prefect, but Sewage Sweeper has a very strange idea of how batteries behave when they are getting close to thermal runaway. He seems to think that they could look perfectly normal and measure out as being barely warmer than their environment, then suddenly heat up to the point of bursting. It doesn\'t work that way. Self-discharge gets worse as the battery gets older, and warms the battery above ambient (which makes it worse), but it does have to get remarkably warm for thermal runaway to set in. Any kind of battery monitoring system will have loads of early warning of this kind of situation and will be insisting that the driver takes the car straight to the nearest service centre long before they could catch on fire.

LOL! You are just FUCKING CLUELESS! Did that Tesla \"warn\" the driver to take it to a service CENTER??? Maybe it sent him a text before it EXPLODED!

Silly question. If it did the driver doesn\'t seem to have paid any attention. The basic point is that batteries don\'t just explode, and properly monitored batteries start getting worryingly warm long before they go into thermal runaway - the threshold for that seems to be above 120 degrees Celcius, which is easily detectable. A clueless twit like you seems incapable of realising what this means.

--
Bill Sloman, Sydney