New to electric questions

| The mah taken out of each cell MUST be the same, and so must teh mAh | put back equal the mAh taken out in every case.

Really? I've found that my Blips do self discharge somewhat. From your description, I understand that yours do not? I don't buy it.

Sure, LiPo self-discharge rates are pretty low -- but they're not zero. I wonder if the self discharge rates vary at all between individual cells? If they do, even a little, then that would completely explain why occasionally balancing your pack helps extend pack life -- either the cell with the highest self discharge rate gets discharged too deeply, or the cell with the lowest self discharge rate gets overcharged.

Reply to
Doug McLaren
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| Really? I've found that my Blips do self discharge somewhat.

Blips? Spell checker must have decided that Blips was a good replacement for Lipos ...

Reply to
Doug McLaren

Not appreciably and not differentially.

I left all my pacsk sitting fully cahrged obver the winter ats a steady sort of 20C temp.

Then recharged tehm all 'just in case' in the spring. None took any charge to speak of..less than 5% of the capacity.

Even if one or another cell was self discahrging 20% faster than another, thats 20% of 50%..1% worst case.

Like I said, if one cell is heavily discharged with respect to another, you already HAVE a problem that a balancer won't fix. It MAY just protect the pack from flames, but it won't restore a damaged pack.

I even checked a pack - 3s - that was left up a tree for a few weeks. It came back sort of..about half capacity, and even that pack was NOT SERIOUSLY OUT OF BALANCE. Just ***ed. :-)

The one thing that helps extend pack life is de-rating them. Run them at less than 8C and never below 3v/cell and they last a LONG time.

I have a suspicion that the cell vendors are only too happy to tell you that you need an expensive balancer, because they are generally vendors for the same, and generally it gives them a let out if their packs don't perform to their claims (none of them do actually, not the one's I've tested)

Reply to
The Natural Philosopher

| I guess I somehow missed your web site on batteries

To be fair, your site barely talks about LiPos, and a quick scan shows that the part that *is* about LiPos was written by other people.

You talk about them more in your column, yes, and on some web forums too, but perhaps your web site itself needs some updating if you want to point to it as evidence of your expertise with LiPo batteries.

If you're going to give qualifications, you have better ones to give.

| or your Curriculum Vitale on the discipline.

It's probably appropriate that you said CV rather than resume. If I understand correctly, you retired long before LiPo batteries came out, and so your experience with them came from the same place as the rest of us -- from actually using them.

| I don't have access to British patents either

Sure you do.

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I'm not arguing with your position regarding balancers -- just pointing out that your statement of your qualifications could be improved.

Reply to
Doug McLaren

He didn't: he said 'Vitale' not 'Vitae'

Which means a 'course of vitality' rather than a 'course of life'.

It appears to be another incorrect usage that has probably spilled over in to Americanese due to the number of Italian and Spanish immigrants, and the lack of classical education and general standards prevalent,.

Plus the American propensity to make words sound as long a possible, to impress the natives.

I mean, whoever invented 'burglarized' when 'burgled' has been in common use for centuries..

Reply to
The Natural Philosopher

Hmm! You really ARE an arrogant prick, aren't you. I hope those words aren't too lengthy for you.

Harlan

Reply to
H Davis

Hmm. see what I mean?

If the cap fits, wear it ;-)

Reply to
The Natural Philosopher

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