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Comment Re:LFP for dummies (Score 1) 74

The voltage out of an automotive alternator can easily get to 15 volts

If it does that, there is a problem. It should never, ever go over 12.65+2=14.65v. That's how electrolyte gets cooked off.

I doubt anyone will claim that LFP can be dropped in everywhere that there is a lead-acid battery

The person I replied to did so.

it's that incompatibility with common 12 volt automotive and other similar devices/systems is not among the reasons to avoid LFP.

Yes, in fact it is a reason to avoid dropping it in anywhere that a flooded battery is used without knowing what you're doing, and I've explained why.

Let us know when you get your A6 or equivalent.

Comment Re:and yet (Score 1) 72

I know this is going to offend, but you do realize that PEX offers a superior result in several regards, right? You can reduce right angles, improving flow. It's far more freeze resistant. It's cheaper to replace when you do have freeze damage — join the old PEX with the new PEX and you can push-pull the new stuff into place if it was installed worth a damn to begin with. The only part I don't like is when people do use crimp bands, those are stupid. Push-fit connectors or Flair-It are far superior as they have much better freeze resistance.

Comment Re:Privacy != privacy (Score 1) 54

If the government thinks someone is a criminal, first, get a warrant, and second, collect data. If it makes life more difficult for law enforcement, well, that's just life in a free society where people have rights.

On one hand, I agree with you. That's how it should work. On the other hand, that ship has sailed. You forgot about PRISM and other unconstitutional citizen spying programs already, huh? Maybe pay attention.

On the gripping hand, this is the court telling them not to delete data because they expect to get a warrant to look at it, so maybe you don't need that onion on your belt after all.

Comment Re:System Restore Is a Hack (Score 1) 48

Meanwhile I'll settle for having a file system that lets you overwrite in-use files without requiring a reboot, like Unix has for decades. I've never understood why NTFS cannot do this.

Can't / Don't want to. They are two different things. If you're aiming for a system with perfect uptime like on servers you may have different priorities than a system with user facing software

That is fundamentally wrong. First of all, both Unix and Windows are used as both workstations and servers, so it's obviously wrong. Second, and slightly less obviously but you're still wrong, you want this functionality on both desktops and servers.

In a world of DLL-hell it's not a question of having the ability to overwrite an in use file, it's a question of what state your system and the applications on it is in afterwards.

You're not selling it. You're saying that their system is so deficient that they have to have it be deficient in another way.

You're asking them to solve a problem they philosophically don't care about,

Uptime? Yeah, we already know Microsoft doesn't care about that. Windows has detected you have moved the mouse, reboot required.

Comment Re:LFP for dummies (Score 1) 74

I wouldn't be surprised if we saw LFP replace most usages of lead acid batteries in the near future since the cell voltage is 3.2V nominal, and you can stack 4 cells to get a 12.8V battery, which would be a drop-in replacement for most lead acid applications.

This isn't true for multiple reasons. First and most importantly, full charge on a 4-cell LFP is 3.6 volts. That means full charge on a nominal 12V LFP is 14.4V. Charging voltage is therefore 14.6V or 14.8V and the details are handled by the BMS. Maximum charging current is also far higher than a six-cell flooded battery, which is fully charged at 12.6V, and where maximum safe charging voltage is about 2V over the current battery voltage. (Yes, some chargers do significantly more voltage — this is bad when done without per-cell temperature sensing which nobody does.) A flooded battery limits current, and charging systems take this into account. Dropping in a LFP might be fine, or it might cause the smoke to come out, and you have to understand the system to know which. Most alternators will burn themselves up, or at best, burn out the fusible link. On some vehicles that's easily replaced, but on most it's a harness repair. You cannot even reasonably charge lithium batteries with all solar controllers designed for flooded cells. Some of them are cheaply made enough that they will again burn themselves up, even cheaper MPPT units though it's mostly just PWM models.

Lithium batteries are great, but you cannot just drop them in to many applications. In others they will work OK, though most "intelligent" battery chargers not designed for them will only charge them to 80%, or will charge to 100% but charging slows to a trickle around 80%, because the charging voltage is incorrect.

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