[RE-wrenches] EG4 Lithium absorb time in open loop configuration

[Steve Higgins]

In my experience, when the LFP batteries are connected in an "Open Loop"
(no comms), you typically want 20-30 minutes per parallel connected
battery. When connected in closed loop comms, you can set this for much
shorter (1/3 to 1/2) as the battery has control over the absorb timers
based on the state of charge of all the individual batteries.

Absorbing for longer will not hurt an LFP that has its own BMS. Still, if
you don't absorb long enough, over time, this will cause an imbalance
between the batteries and eventually could cause the lower batteries to
crater under a surge load.



<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
<http://www.rollsbattery.com> <http://www.rollsbattery.com>
Steve Higgins ⋅ Technical Services Manager
t +1.902.597.4020  m +1.206.790.5840
f +1.902.597.8447  e steve at surrette.com
<http://www.facebook.com/RollsBattery>
<https://www.youtube.com/user/RollsBattery>
<https://www.youtube.com/RollsBatteryEngineering>
<https://www.youtube.com/RollsBatteryEngineering>
<https://www.youtube.com/RollsBatteryEngineering>
<https://www.linkedin.com/company/rolls-battery-engineering>
<https://www.linkedin.com/company/rolls-battery-engineering>
<https://www.linkedin.com/company/rolls-battery-engineering>
<http://www.instagram.com/RollsBattery>
<http://www.instagram.com/RollsBattery>
------------------------------
CONFIDENTIALITY: The information transmitted herein is intended only for
the addressee and may contain confidential, proprietary and/or privileged
material. Any unauthorized review, distribution or other use of or the
taking of any action in reliance upon this information is prohibited. If
you receive this email in error, please contact the sender and delete or
destroy this message and all copies.
------------------------------


On Thu, Nov 7, 2024 at 4:47 PM Carl Hansen via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> Jeremy,
>
>    Signature solar techs have told me 30 min.
>
>   Carl Hansen
>
>   Hansen&Sun Elect.
>
> On 2024-11-07 6:31 AM, Jeremy Rodriguez via RE-wrenches wrote:
> > Wrenches
> > Signature Solar has no absorb time recommendation for their rack mount
> EG4s !
> > I’m setting up a system with a 1200 ah battery stack.  Six in parallel.
> > What would be a good absorption time? No battery comms to CCs
> > 5925  wPV
> >
> >
> > Jeremy Rodriguez
> > Solar Installation / Design
> > All Solar, Inc.
> > 1453 M St.
> > Penrose Colorado 81240
> >
> > Sent by Jeremy's iPhone. Sorry for typos and shorthand.
> > _______________________________________________
> > List sponsored by Redwood Alliance
> >
> > Pay optional member dues here: http://re-wrenches.org
> >
> > List Address: RE-wrenches at lists.re-wrenches.org
> >
> > Change listserver email address & settings:
> > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
> >
> > There are two list archives for searching. When one doesn't work, try
> the other:
> > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
> > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
> >
> > List rules & etiquette:
> > http://www.re-wrenches.org/etiquette.htm
> >
> > Check out or update participant bios:
> > http://www.members.re-wrenches.org
> >
> _______________________________________________
> List sponsored by Redwood Alliance
>
> Pay optional member dues here: http://re-wrenches.org
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> Change listserver email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
>
> There are two list archives for searching. When one doesn't work, try the
> other:
> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
>
> List rules & etiquette:
> http://www.re-wrenches.org/etiquette.htm
>
> Check out or update participant bios:
> http://www.members.re-wrenches.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20241107/123781b1/attachment.htm>