6v 8GGC2 Battery - is this Gel Cell?

[BigAl.NZ]

Good to know. Fully charged at rest should be ...? 13.2?

[john61ct]

As stated 12.85V at rest is 100% Full.

May show a bit higher with surface charge.

Originally Posted by john61ct

Yes GEL by East Penn aka EPM Deka

Datasheet:
http://www.eastpennmanufacturing.com...eters-1913.pdf

Developed by Sonnenschein, nearly as good.

Low charge rate, takes 7+ hours to get from depleted to Full, stop at endAmps .005C, at least 12.85V at rest.

Can last a **very** long time if well coddled, kept cool.

Can go below 50% DoD if needed, but better longevity if you don't.

[john61ct]

This chemistry does **not** last long if regularly overcharged, or at too high a rate, or in an overtemp engine room.

Should **definitely** not charge at over 14.2V

[newhaul]

Originally Posted by john61ct

Yes GEL by East Penn aka EPM Deka

Datasheet:
http://www.eastpennmanufacturing.com...eters-1913.pdf

Developed by Sonnenschein, nearly as good.

Low charge rate, takes 7+ hours to get from depleted to Full, stop at endAmps .005C, at least 12.85V at rest.

Can last a **very** long time if well coddled, kept cool.

Can go below 50% DoD if needed, but better longevity if you don't.

you need to read the technical before you post your opinions and I would have to assume the charge voltage you state is your opinion due to not even being close to what the spec sheet you linked to . The manufacturer even says to float at 13.44 volts minimum.
See attached chart .

[newhaul]

Originally Posted by john61ct

This chemistry does **not** last long if regularly overcharged, or at too high a rate, or in an overtemp engine room.

Should **definitely** not charge at over 14.2V

again you need to read the spec sheets
It calls for absorption at 144.4v and
Equalization between 14.4- 14.6 volts

[newhaul]

Originally Posted by newhaul

again you need to read the spec sheets
It calls for absorption at 144.4v and
Equalization between 14.4- 14.6 volts

absorption is 14.4v not 144.4v

[john61ct]

I stand by what I wrote, feel free to call them to discuss.

Same misunderstandings as with LFP.

The maximum they can tolerate without being damaged

is not what they should ideally receive for good longevity. Overcharge murders them, best too the minimum required to get them resting at 12.80-12.85V.

[BigAl.NZ]

Originally Posted by newhaul

again you need to read the spec sheets
It calls for absorption at 144.4v and
Equalization between 14.4- 14.6 volts

So looking at that spec sheet:

30% C20 (180Ah) = 54Amps Max
Absorption : 14.1v
Float = 13.44v
Equalize = 14.4v

Just checking I have read this right.

Also if the batts are living next to engine, it will be a lot higher than 25C. More like 50C.

[john61ct]

Lower current amps

and Float at 13.2V

would be better for longevity

[newhaul]

Originally Posted by BigAl.NZ

So looking at that spec sheet:

30% C20 (180Ah) = 54Amps Max
Absorption : 14.1v
Float = 13.44v
Equalize = 14.4v

Just checking I have read this right.

Also if the batts are living next to engine, it will be a lot higher than 25C. More like 50C.

those are the minimum numbers according to the manufacturers engineers yes

[newhaul]

Originally Posted by john61ct

I stand by what I wrote, feel free to call them to discuss.

Same misunderstandings as with LFP.

The maximum they can tolerate without being damaged

is not what they should ideally receive for good longevity. Overcharge murders them, best too the minimum required to get them resting at 12.80-12.85V.

what you wrote is wrong according to the manufacturers specifications .

[john61ct]

Found another note and past email from EPM tech support.

https://i.imgur.com/abbYgVX.jpg

14.0 - 14.1 best voltage setpoint

0.16C is max charge rate

Taper drops to 0.08C is 80%

endAmps at 0.015C is better for normal cycling, sufficient to get to

resting OCV of 12.9V is 100% Full, but

if below protocol completed, surface charge may be as high as 13.1V.

0.005C is really for capacity testing, max 100% SoC benchmark, and below protocol

_____
Rather than equalizing periodically, better approach for anti-sulfation is a more frequent "finish charge" just after endAmps point

raising voltage to 15.3 for a brief time, stopping point in tapering amps held longer depending on PSOC conditions vs frequency of the opportunity to complete this protocol.

[BigAl.NZ]

I rang East Penn and got the spec sheet for 8GGC2:

https://drive.google.com/open?id=1Zv...tA4sRuvPHqiV5a

It differs from the charging spec sheet earlier in this thread. I note that both spec sheets do refer to 8GGC2.

If I compare the differences it looks like in this image.

Interesting that the values don't correlate.

Where is the truth? Thoughts?

I am inclined to go with the lower (conservative) voltages since I am operating at higher than 25 deg C.

Cheers

AG

[john61ct]

Originally Posted by BigAl.NZ

I rang East Penn and got the spec sheet for 8GGC2:

https://drive.google.com/open?id=1Zv...tA4sRuvPHqiV5a.
Where is the truth? Thoughts?

Go with the most recent advice / data sheet, manufacturers do revise their specs as they gather new data over time.

While you're in communication with them, ask specific questions, some specs the low end of a range are better, others the higher side.

> I am inclined to go with the lower (conservative) voltages since I am operating at higher than 25 deg C

All voltages given are subject to a specific temperature adjustment curve.

Quality charging gear takes care of that automatically, but as always verify with your own known-accurate instruments independent of any charge source, SoC meters etc.

[BigAl.NZ]

Originally Posted by john61ct

Quality charging gear takes care of that automatically, but as always verify with your own known-accurate instruments independent of any charge source, SoC meters etc.

Yes quality charging gear helps - the alternator regulator is the MC612, but even with this there are several settings which is suggests to set manually :

http://www.balmar.net/wp-content/upl...-2005-2009.pdf (page 10)

I have also decided going forward to protect the investment (and given the proximity to the engine bay) to get two of these :

https://www.victronenergy.com/access...-battery-sense

That way I can add temperature to my BMV712.