Indefinitely prevented from riding

[The Brahan Seer]

1 hour ago, Cerbera said:

They thought it was a crazy video as I recall

Good point, not the idea itself. 

1 hour ago, Cerbera said:

I do hope the response Begode got didn't discourage them from keeping on trying !

I think in the short term it will have but the pressure to try again will happen as we keep getting forced out.

49 minutes ago, chanman said:

They want the same range and power output from the same size pack, which wasn't going to happen, and putting it on the RS, a model typically used for high performance activities, was doomed to failure to meet expectations. 

Yes it wasn't the best wheel to test the idea on.

53 minutes ago, chanman said:

A somewhat widespread policy of "only LFP packs on PEVs in this building", as unenforceable as it may seem now, might actually be what is needed to shift the market in order to get people to accept the worse performance, especially for commuter wheels.

Yes , I would much rather have a wheel I can take on public transport, store without any hassles and have the peace of mind knowing my house is less likely to burn down. Worth the trade off with power/ range. It would only be for a few years too.

Some advantages over and above the safety is the increased life span (charge cycles) and durability so although we might need to charge more often the batteries will last as long or longer then our current ones. Plus they are cheaper too. 

 

[techyiam]

3 hours ago, chanman said:

A somewhat widespread policy of "only LFP packs on PEVs in this building", as unenforceable as it may seem now, might actually be what is needed to shift the market in order to get people to accept the worse performance, especially for commuter wheels.

This could be done at the appartment building level, or city hall can make this a city-wide bylaw, I suppose. Then it will drive up the demand.

But then that means the decision has been made to regulate and not ban.

[mhpr262]

On 4/14/2023 at 9:44 AM, Chriull said:

A continuous trickle charge would cause plating of metallic lithium and compromise safety. To minimize stress, keep the lithium-ion battery at the peak cut-off as short as possible." 

Frankly I have no idea how that is supposed to work. A 20 cell battery has a voltage of 84V when fully charged. A fully functional charger for that pack delivers exactly that voltage or slightly below. When it has finished charging and the batteries are full that means the pack has exactly the same voltage as the charger so that should mean is physically impossible for current to keep flowing. There is no "trickle charging" or whatever they mean by that. No voltage differential means no charging can and will take place, trickle or otherwise.

Maybe they are confusing it with the low-self-discharge, superlattice nickel-metal hydride batteries like the Sanyo eneloops? Those do indeed react poorly to constant trickle charging, which is the reason why using them in cordless phones in one's home kills them off pretty quickly. 

[alcatraz]

I think there's voltage sag when charging. So even if the control board reads 84v that's above the real voltage = some trickle is going on. (If you disconnect charging and the voltage settles to 83.5v then you've got 0.5v causing a trickle)

But on the other hand the bms cuts off charging over x voltage. So maybe this anti-trickle feature isn't in the power adapter but in the bms, or both. 

The question is, does the bms keep charging off or renables it after the voltage has settled under the voltage limit? I'd guess it's reenabled.

[Roadpower]

I don't believe that addressing technical nuances is going to help us. I'm NOT saying that there shouldn't be talk about those aspects. I think we are damned by the following fundamental issues.

The e-bikes being used commercially obviously undergo a great many more charging cycles and physical abuse in the form of all the miles they're putting on and the commensurate physical shocks that the equipment is subject to. I have to assume that the charging conditions aren't anywhere near as measured as we would like. These aspects are out of our control and have now been taken head-on by landlords, and I'm sad to say that it is very likely that landlords are doing what they can to get legislators to take it to the next step.

The most significant issue is the battery tech itself. I think most of know that there are numerous entities working on solutions in which the battery tech is fundamentally not a lurking fire hazard. This is where we are in limbo, we are at the mercy of fate and time. I believe that in time that tech will come but for some of us (namely older riders) it won't matter.

I don't believe that trying to appeal with use case arguments or who is better suited to care for their PEV is going to help us either. Hammers are a very blunt instrument, they are not a scalpel. We're getting hit with a hammer by people who care not about limiting damage with a scalpel.

Edited April 16, 2023 by Roadpower

[Circuitmage]

On 4/13/2023 at 5:06 PM, Cerbera said:

Christ, I hope not - 1% fire rate could only be considered a catastrophic failure ! Even 0.1% would be unacceptable risk. 0.01% is still too many !! I would hope the rate is lower than ALL those figures !! 

 

I agree. 1% would be crazy bad, but from all the talk on here I don't know what the actual numbers are.

In manufacturing I know you have a thing call DPMO (Defects Per Million Opportunities). Ideally you want that to be zero, or as low as possible. In reality (having worked in electronics manufacturing for a while) I have seen that rate frequently somewhere between 1000 and 10000....and other things happen that raises that number even higher. Sad but true. As a test engineer, fires I used to put out were in the 3% failure range.

[0000]

On 4/15/2023 at 7:23 PM, Roadpower said:

...

I don't believe that trying to appeal with use case arguments or who is better suited to care for their PEV is going to help us either. Hammers are a very blunt instrument, they are not a scalpel. We're getting hit with a hammer by people who care not about limiting damage with a scalpel.

Very well said. It's sad and ironic that the places where people can benefit the most in all sorts of ways from PEV transportation are in the process of expediting the seemingly inevitable hammer-type legislation. Besides the more immediate threat of banning PEV devices wholesale, it's not inconceivable that one day even individual battery cell sales which are popular for battery pack builds will be regulated in some way requiring licensing for purchase, and in effect, making them less or not available altogether to the general public.

It's pretty clear that we live in a world where the idea of safety, particularly the kind packaged in promises made by government officials and other perceived authorities, is preferred by the public at large in almost every perceivable arena to even the notion of preference for freedoms and liberty of the individual. Worse, when they're not wrong in this case, particularly in high-density living scenarios regarding the risks of widespread lithium-ion battery chemistry use, the reality of some overseas design, production, and Q&A (onshore can be just as bad), and how PEVs powered by lithium-ion batteries are sometimes handled in "hard-use" cases.

It's not even a given that future, higher-density battery chemistries would be necessarily be safer, as logically it would follow that an increase in energy per given volume would also tend to increase the instability or volatility of such future chemical arrangements* ^{commenting as a layman, not a material scientist or chemist}. You couple this with a lot of other trends going on in the world such as people appearing to trend toward being less capable of assessing and making appropriate risk-tolerance decisions, the voting public's' desire to outsource individual accountability and treat their governments as a perpetual parental entity, the lack of nuance in public discussion over a majority of controversial issues and mass media's long-standing campaign that has served in bringing down the level of public discourse to: this thing bad = destroy, this thing good = endless support, and the direction PEV legislation will go seems virtually inevitable. Where, as you say, we PEV supporters are at the mercy of fate and time, observing a process with an almost predetermined trajectory.

In-advisably, if an individual renter wanted to assume 100% responsibility at all times, even in the event of a catastrophic failure, they could try and hide their small or medium-sized wheel in a travel bag and attempt to duck surveillance. However, rented housing and particularly high-density housing that has explicitly banned PEVs, well, just imagine the potential downsides if something goes horribly wrong. Few if anyone would be on your side, and it's probably not worth the risk, much less without regularly taking some kinds of safety precautions with use and storage.

Like I said, sad and ironic that where PEVs are best suited, they are presenting as a noticeably elevated (fire) risk to public welfare due to a whole bunch of complicating factors which don't fit into the range of sound-byte public discourse public opinion is shaped and managed by.

Edited April 18, 2023 by Vanturion

[Toad]

Today I stumbled on the genre of YT videos about refrigerators suddenly exploding.  This changes everything!

You might ask your local legislative representatives about strengthening the building code.  Builders should equip residences with better firewalls.  If your neighbors are bothered when your PEV bursts into flame, how is that your fault?  It is their own fault for overpaying for a residence of outdated construction.

In the meantime, removable batteries would clear an obstacle to Lyft / Lime / Spin dockless unicycles so more people could use them without needing to keep them indoors.