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Higher the amps and voltage, the more careful you should be, disconnect soon as it hits your target, IMO 13.8v.

No need to hold Absorb, better not to at all above that point.

And only fill when you plan to use them, healthier to keep at low SoC if not being cycled
 

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Lithium-ion is a very general category, includes dozens of different specific chemistries, each with its own specs.

I only deal with LiFePO4 myself, and looks to me like that's not what you're talking about, so I'm not your man.
 

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If FLA is rated 11.2 - 15V, then four in series would be 60V max. Is this a problem for 48V devices?
The *charging* profile varies by batt vendor and product line.

A given *load* device will have its own specs.

I take all loads offline when equalizing an FLA bank, that's the only time they'll see high voltages, depends on temp but some mfg spec 15.5+V.

Extrapolated to 4s yes that is 62+V, and yes many electronics would be too sensitive to stand that.

I think generally 14.75V, or 59V would be a reasonable upper limit.


Since I charge LFP at 3.45V max, 4s is 13.8V max, at 16s 55.2V max, so well within safe margin. I might get up to 14V or so for maintenance routines, also safe at 56V.
 

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Is 60V max acceptable in a "48V standard"?
Pushing the above by only 1V, but likely OK.

Really need to check the specs of the device(s) you're concerned about.

If this is indeed LFP, why the heck are you pushing charge volts so high? Sacrificing IMO many hundreds of life cycles off the back end, for very little gain in AH capacity. Of course the batt maker will be happy about your doing that. . .
 

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the 12V standard demands that all devices be able to operate from 11V to 15V. If they cannot operate at 15V, then they cannot call themselves a 12V (automotive) device, and if it break at 15V, then the purchase must be refunded.

If a motor controller maker claims to have a 12V controller, then it must handle 15V, otherwise it is false advertisement.
What international government or industry body created and enforces this standard?

Sounds like fantasy spun from whole cloth to me.

Links?

Perhaps some sort of informal de-facto understanding.

I doubt respected by the factories in third world countries making most such devices these days.

But IMO just multiply by 4 to generalize, but check the mfg specs for any important or expensive device you plan to buy, the tolerance range is often spelled out in the tech docs.
 
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