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Batteries: How cheap can they get?

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Re: Batteries: How cheap can they get?

#281

Post by vel0city »

ssl-3 wrote: post #279
vel0city wrote: post #276

Earlier quoted context omitted.

You're either not going to have much meaningful backup power or you're not going to have much usable range if your plan is based on consuming the energy on your car while holed up and also using that energy to potentially drive a couple hundred miles. That's my real point here.

It depends on what "meaningful backup power" is. If I had an EV that I could use to run house-sized stuff with, and the power were off for an indefinite time due to a storm or something, then I'd like to think that I'd use that EV just as sparingly as I would my little Jackery device and portable solar panel (that I can coax at most about 80W from on a perfectly-sunny day). I can use my rig to [sparingly] run some li…

I've actually been through multiple evacuations before, and practically every mile of energy in our vehicles counted. One time one of our cars literally ran out gas rolling into the first gas station with fuel after leaving with a full tank. When major storms are coming my cars stay topped off and don't get touched except for very purposeful reasons.

And given the fact it might be harder to find a working and available charger while leaving in an emergency I wouldn't want to rely on finding one along the way to wherever I'm going.

Re: Batteries: How cheap can they get?

#282

Post by nanomonkey »

cyberax wrote: post #273
nanomonkey wrote: post #212

Earlier quoted context omitted.

Are you suggesting using a DC Optimizer from your solar panels to charge 48V batteries directly? This would be interesting. It's the first I've heard of optimizers being used for anything other than prior to an inverter.

You absolutely can do that. You still need a charging controller and a BMS, obviously. But you can avoid the AC round-tripping.

Nice, the 48V batteries I have already have BMS's...any suggestion for a nominal 48V DC optimizer and charge controller?

Re: Batteries: How cheap can they get?

#283

Post by vel0city »

Dylan16807 wrote: post #278
vel0city wrote: post #276

Earlier quoted context omitted.

You're either not going to have much meaningful backup power or you're not going to have much usable range if your plan is based on consuming the energy on your car while holed up and also using that energy to potentially drive a couple hundred miles. That's my real point here.

Do you have a destination in mind within a couple hundred miles? I hope you're not setting up to get stranded on the highway. I think I'd be sorting weather events into two buckets: "I can get somewhere that wasn't hit hard with 50-100 miles of range" or "I need to travel a distance measured in states and refueling will be needed". So the difference between "full battery" and "half battery" is pretty tiny, and I can…

Waco is a bit over 100 miles from me and would be a potential destination for me in an emergency. It'll probably be massively slammed though if all of DFW needs to evacuate for some reason. Austin is then over 200mi.

Oklahoma City is a bit over 200 miles if I needed to go to the city the next state over. Shreveport is just under 200mi.

If something is making me leave DFW then 50mi isn't going to get me anywhere. That's not even going across the metro area.

Re: Batteries: How cheap can they get?

#284

Post by Dylan16807 »

vel0city wrote: post #283
Dylan16807 wrote: post #278

Earlier quoted context omitted.

Do you have a destination in mind within a couple hundred miles? I hope you're not setting up to get stranded on the highway. I think I'd be sorting weather events into two buckets: "I can get somewhere that wasn't hit hard with 50-100 miles of range" or "I need to travel a distance measured in states and refueling will be needed". So the difference between "full battery" and "half battery" is pretty tiny, and I can…

Waco is a bit over 100 miles from me and would be a potential destination for me in an emergency. It'll probably be massively slammed though if all of DFW needs to evacuate for some reason. Austin is then over 200mi. Oklahoma City is a bit over 200 miles if I needed to go to the city the next state over. Shreveport is just under 200mi. If something is making me leave DFW then 50mi isn't going to get me anywhere. That…

What event do you have in mind that very badly affects your location but not those cities, and you don't realize driving there is a good idea until a day or two after the event?

Re: Batteries: How cheap can they get?

#285

Post by ssl-3 »

vel0city wrote: post #281
ssl-3 wrote: post #279

Earlier quoted context omitted.

It depends on what "meaningful backup power" is. If I had an EV that I could use to run house-sized stuff with, and the power were off for an indefinite time due to a storm or something, then I'd like to think that I'd use that EV just as sparingly as I would my little Jackery device and portable solar panel (that I can coax at most about 80W from on a perfectly-sunny day). I can use my rig to [sparingly] run some li…

I've actually been through multiple evacuations before, and practically every mile of energy in our vehicles counted. One time one of our cars literally ran out gas rolling into the first gas station with fuel after leaving with a full tank. When major storms are coming my cars stay topped off and don't get touched except for very purposeful reasons. And given the fact it might be harder to find a working and availab…

I'm confused.

If you're part of an organized evacuation, you're doing this before the storm -- correct?

And if that's the case, then: It doesn't matter how long an EV will or will not run the stuff inside of your home, because you won't be there.

Re: Batteries: How cheap can they get?

#286

Post by vel0city »

Dylan16807 wrote: post #284
vel0city wrote: post #283

Earlier quoted context omitted.

Waco is a bit over 100 miles from me and would be a potential destination for me in an emergency. It'll probably be massively slammed though if all of DFW needs to evacuate for some reason. Austin is then over 200mi. Oklahoma City is a bit over 200 miles if I needed to go to the city the next state over. Shreveport is just under 200mi. If something is making me leave DFW then 50mi isn't going to get me anywhere. That…

What event do you have in mind that very badly affects your location but not those cities, and you don't realize driving there is a good idea until a day or two after the event?

The 2021 Texas ice storm and related power outages would have been one where driving to Oklahoma City or Shreveport would have been a place to go to. That also would have significantly reduced that theoretical 230ish mile range of a Lightning or similar EV.

Lake Dallas dam breaking after major flooding in the Trinity River would cause quite a bit of destruction in DFW and potentially make things pretty unlivable around here and force a lot of people out of here and into the surrounding areas. Also an event that wouldn't necessarily be seen days ahead of time.

I grew up in South Houston, so I had a number of times of hurricanes coming through and not necessarily destroying my house but making the surrounding areas pretty unlivable for days to weeks. Maybe it gets cleaned up enough in a couple of days, maybe it doesn't.

Re: Batteries: How cheap can they get?

#287

Post by vel0city »

ssl-3 wrote: post #285
vel0city wrote: post #281

Earlier quoted context omitted.

I've actually been through multiple evacuations before, and practically every mile of energy in our vehicles counted. One time one of our cars literally ran out gas rolling into the first gas station with fuel after leaving with a full tank. When major storms are coming my cars stay topped off and don't get touched except for very purposeful reasons. And given the fact it might be harder to find a working and availab…

I'm confused. If you're part of an organized evacuation, you're doing this before the storm -- correct? And if that's the case, then: It doesn't matter how long an EV will or will not run the stuff inside of your home, because you won't be there.

When did I say organized? And evacuations can happen before and after an emergency. Evacuating just means leaving the unsafe place for a safe space, it doesn't define the order of things. I've evacuated before and after major storms depending on the circumstances at the time.

Leaving a burning building is still evacuating the burning building. Evacuating a burning building doesn't mean it's an orderly thing before the fire starts.

Re: Batteries: How cheap can they get?

#288

Post by gambiting »

LorenPechtel wrote: post #274
whatevaa wrote: post #272

Earlier quoted context omitted.

HDMI cables? Sounds like protectionism. Invent rules to make yourself more work.

Aren't there power delivery versions of HDMI? I can understand requiring a license for any power wires behind walls. I could also see the possibility that it's just an old law that doesn't consider data-only cables which don't have the safety issues that wires carrying power do.

It's definitely an old law that never took data cables into account, but the current interpretation is that any cable that carries electrical current has to be installed and certified by an electrician.

Re: Batteries: How cheap can they get?

#289

Post by AtlasBarfed »

Aurornis wrote: post #29

This blog post is all over the place. The 2030 price projections are taken from extrapolations of Lithium battery costs, but he’s assuming Sodium chemistry batteries will take over and become ubiquitous at rock bottom prices. The first Sodium batteries barely became available within the past year. He’s also treating batteries like the only component of the system. The associated charging, inverter, and physical struc…

Sure, it'd be great if all the little bumps in the road were already hammered out, but that we all know that's not how massive scale production works.

The two biggest numbers you need to look at in that article are lfp at 200 wh per kilogram and sodium ion at 160 w per kilogram.

Keep in mind that I believe neither lfp or sodium ion needs extensive amounts of cooling like Cobalt nickel batteries and their runaway fire problems. So their pack density is actually better and simpler.

So the 200 watt hour per kilogram basically equates to a 300 to 400 mile and possibly a 500 mile range car depending on efficiencies.

160 watt hour per kilogram sodium ion is the 200 to 300 and possibly 400 car

When you think about it that way consider the implications for electrifying all consumer transportation. The sodium ion density means that the city car that would serve possibly 4 to 5 billion people in the world is a solve technology, borrowing proper scaling.

The lfp density implies probably another billion to 2 billion people that need slightly better range, assuming good infrastructure for recharging.

Now the road maps for lfp and sodium ion. Both are going to probably increase by at least 20% in the next 2 or 3 years. Maybe 5 years tops.

If they can figure out sulfur chemistry versions of lithium sulfur and sodium sulfur then you may be able to double or triple densities in the next 10 to 15 years.

This is all very very revolutionary stuff.

Re: Batteries: How cheap can they get?

#290

Post by cyberax »

jseutter wrote: post #174
cyberax wrote: post #117

Earlier quoted context omitted.

Do you know if these batteries be used as a replacement for batteries of a lead-acid UPS? I have a Tripp-Lite rack-mount UPS with an extension battery, but its battery has degraded and it can only sustain my computing load for 3-4 hours. It'd be great to replace it with an LFP battery.

You can't use LFP batteries as a direct replacement in your UPS, no. The voltages and charge characteristics are different. What you can do is replace the UPS with a portable battery solution, like another poster suggested. I believe the Anker units are one of the few that can function as a UPS. Most sorta-can, but the key difference most of them lack is that they don't turn on automatically after fully discharging w…

I actually had a good experience replacing a lead-acid backup battery with an LFP battery in my garage door opener. I guess if the battery has an internal BMS and can accept charge at 52V, it might be enough?
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