[RE-wrenches] Outback FXR: Battery voltage exceeds settings

Sat Jul 23 08:27:18 PDT 2022

Most AGM's don't like voltage that high and it swells the battery and
destroys its storage capability alot of the time
Jerry

On Fri, Jul 22, 2022, 7:50 PM Steve Higgins via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> William,
>
> If the battery cases swelled, they saw over 52 degrees C temps for quite
> some time.
>
> While the swelling is usually only cosmetic, what's happening inside is
> the negative plates are starting to burn. This is where you will start to
> lose capacity and life cycle...  Extended temps of just 35C will half the
> overall battery life.
>
> One of the issues with the Outback gear is they only temp compensate at
> 5mv/Degree/cell. For all the AGM batteries I know of, you need to temp
> compensate at 4mv.   In hot temps, this should help, but cold temps could
> result in an overcharge.   Did you check the BTS and make sure it was
> operating properly?
>
> Another issue is that BTSs are often placed on the top or lug of the
> battery,   The top of the battery is about 5-10 deg C cooler than 1/2 way
> down the side of the battery, Which will also cause problems with proper
> temperature compensation, especially with warmer/colder extremes.
>
> Any kind of sulfation will cause an imbalance when you mix old and new
> batteries.   I'm not a fan of mixing any age AGM batteries as there is no
> way to tell what the SOC of the old bank vs. the new bank is.   They are
> not like flooded batteries; you can check SGs and dissipate heat
> much better than AGM or GEL batteries.   I discourage doing this if you
> can.   I probably wouldn't have mixed the old and new in the same strings.
> This way, you keep the higher resistance batteries in a single string,
>
> Lastly, bunching them together with no spacing between them is very bad.
> Batteries should be in a cool, dry environment.  Most battery companies
> want to see 1-3 inches in between each battery to allow for effective
> cooling. When they are all bunched up together, that is a lot of thermal
> mass that doesn't have much chance of cooling.   I have seen two parallel
> strings of AGMs take 24-36 hours with no charging or load to drop from 45c
> to 25C!
>
> Hope this helps!  Have a good weekend.
>
>
>
>
> <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
> <#m_-3124562702126219588_SignatureSanitizer_SafeHtmlFilter_>
> <http://www.facebook.com/RollsBattery>
> <http://www.facebook.com/RollsBattery>
> <http://www.twitter.com/RollsBattery>
> <https://www.youtube.com/user/RollsBattery>
> <https://www.linkedin.com/company/rolls-battery-engineering>
> <http://www.instagram.com/RollsBattery>
> <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 Fri, Jul 22, 2022 at 6:48 PM William Miller via RE-wrenches <
> re-wrenches at lists.re-wrenches.org> wrote:
>
>> Friends:
>>
>>
>>
>> I maintain a system with 16 AGM L-16 batteries.  Eight were installed in
>> September of 2021 and 8 were added in March of 2022.  This is 5 months
>> apart.  I have understood that when you install a string of batteries you
>> have one year in which to add another string before the first string ages
>> to the point it is contraindicated.  When I added the second 8 I put 4 new
>> batteries and 4 old batteries in each string.
>>
>>
>>
>> About a third of the batteries are discovered to bulging on top.  I
>> assume this means the batteries are damaged.  I checked the FXR and Outback
>> Extreme Charge controller settings and all were set to absorb at 58.8, and
>> float at 55.2, as the manufacturer recommends.
>>
>>
>>
>> I downloaded the charge controller log and got 129 days of data.  In that
>> log I see 68 days where the batteries exceeded 60 VDC. This is over half
>> the days.
>>
>>
>>
>> I wonder this:
>>
>>
>>
>> 1.   Why did the voltage go up above 58.8 on so many days even though it
>> was set at 58.8. (I set the EQ voltage at 58.8 just in case, but EQ was
>> never engaged.)
>>
>> 2.   Did the excess voltage damage the batteries?
>>
>> Any input is appreciated.
>>
>>
>>
>> Sincerely,
>>
>>
>>
>> William Miller
>>
>>
>>
>> Miller Solar
>>
>> 17395 Oak Road, Atascadero, CA 93422
>>
>> 805-438-5600
>>
>> www.millersolar.com
>>
>> CA Lic. 773985
>>
>>
>>
>>
>> _______________________________________________
>> 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/20220723/b156d931/attachment.htm>