myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website myHanse.com - Hanse Yacht Owners Website

Welcome to myHanse.com the forum for Hanse Yachts owners throughout the world.

Forum Home Forum Home > Hints and Tips > 385
  New Posts New Posts RSS Feed - House Batteries
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

House Batteries

 Post Reply Post Reply Page  123 4>
Author
Message
Manyata View Drop Down
Lieutenant Commander
Lieutenant Commander


Joined: 31 December 2013
Location: Lowestoft, UK
Status: Offline
Points: 52
Post Options Post Options   Thanks (0) Thanks(0)   Quote Manyata Quote  Post ReplyReply Direct Link To This Post Topic: House Batteries
    Posted: 29 May 2017 at 18:45
Hi All

I have 2x Victron AGM 165AH Batteries - total 330 AH. They are the original batteries from when the boat was delivered (May 2013) so they are now 4 years old. 

First good sail of the season the other day... 90 mile passage. I was only about half way through the journey (about six hours in)... the voltage on my Victron BMV-702 was showing the batteries as 12.2v... the BMV showed that only 40 Amp Hours had been consumed. The 12.2v seems very very low. This is the lowest I have ever seen the voltage after such a short time and low amount of AH used. I can't see that after just 40 Ah consumed - the V should be so low.

Is it just a simple case of 'they have severed me well' and need to be replaced ? Is 4 years a reasonable life for these ? They have powered me through thousands of miles over the last 4 years.

Also - be interested to know what the 50% used Voltage is on AGM batteries - I see conflicting info on the web. 

Thanks

Tim

Back to Top
Brufan View Drop Down
Commadore
Commadore
Avatar

Joined: 16 December 2010
Location: Belgium
Status: Offline
Points: 437
Post Options Post Options   Thanks (0) Thanks(0)   Quote Brufan Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2017 at 19:03
I have one Victron AGM 165 Ah house battery since delivery in June 2011.
It's still hold its charge and does the job.
You worry too much.
AGM lifetime is between 8-10 year average (vs lead acid batteries lifetime approx 5-6 years)
Bruno

hanse 355 - 57

S/Y Spicy Ginger

White hull, 2 cabins, Volvo D1-30, Selden rig, removable mainsheet track system (modifications done now), Simrad-Jefa autopilot.
Back to Top
Manyata View Drop Down
Lieutenant Commander
Lieutenant Commander


Joined: 31 December 2013
Location: Lowestoft, UK
Status: Offline
Points: 52
Post Options Post Options   Thanks (0) Thanks(0)   Quote Manyata Quote  Post ReplyReply Direct Link To This Post Posted: 29 May 2017 at 19:06
Thanks Bruno - that will do for me !

Just curious - what Voltage do you let your batteries go down to ? I see so much on the web about not letting them go below 50% or they get damaged.

Thanks, Tim
Back to Top
Brufan View Drop Down
Commadore
Commadore
Avatar

Joined: 16 December 2010
Location: Belgium
Status: Offline
Points: 437
Post Options Post Options   Thanks (0) Thanks(0)   Quote Brufan Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 09:30
Originally posted by Manyata Manyata wrote:

Thanks Bruno - that will do for me !

Just curious - what Voltage do you let your batteries go down to ? I see so much on the web about not letting them go below 50% or they get damaged.

Thanks, Tim

I never allow voltage to drop under 12,00 - 12,10 V.  Then I start engine.  Volvo alternator outputs max 115 Ah. So charging usually takes half an hour max.
Usually with one 165 Ah house battery It can stand approx 8 -10 h during navigation with autopilot steering, all instruments on and two fridges.  At anchor, 16 - 24 hours.
Bruno

hanse 355 - 57

S/Y Spicy Ginger

White hull, 2 cabins, Volvo D1-30, Selden rig, removable mainsheet track system (modifications done now), Simrad-Jefa autopilot.
Back to Top
Sea-U View Drop Down
Commadore
Commadore
Avatar

Joined: 14 September 2012
Location: Norway
Status: Offline
Points: 359
Post Options Post Options   Thanks (0) Thanks(0)   Quote Sea-U Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 09:45
Last year I changed the two original batteries from 2008. Changed into two cheap lead acid.
I regret this very much. The old ones worked much better than the new ones.
I just assumed they where too old.

I have now changed to one AGM 350Ah. Hope I will be happy :-)

Sea-U is a 370e #532 located SW Norway
Back to Top
Mark&Catherine View Drop Down
Admiral
Admiral
Avatar

Joined: 18 January 2013
Location: Turkey
Status: Offline
Points: 1058
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mark&Catherine Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 09:58
Victron has some very good download pdfs on their web site.

For AGM batteries the depth of discharge seriously affects the number of cycles (charge and discharge) that the batteries will manage in their life. This is the most significant affect on life, another being temperature.

So is a battery is discharged to 70% its capacity (so only 30 % used ) it will last 1500 cycles.
If it is discharged to 50% (half used) it will last only 600 cycles
If it is discharged to 80% (4/5 used) it will last only 400 cycles.

The voltage for these discharge points are

75 % left. 12.45 volts
50 % left 12.24 volts
25% left 12.06 volts.


So for a good battery life, don't let your battery drop below 12.4.

12 is way too low and will wreck your batteries quickly

The document you need is called energy unlimited, on the victron website.

Mark


385 ubulukutu sail number GBR 3350L in Turkey and Greece with Mark and Catherine
Back to Top
Mark&Catherine View Drop Down
Admiral
Admiral
Avatar

Joined: 18 January 2013
Location: Turkey
Status: Offline
Points: 1058
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mark&Catherine Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 10:17
There is also a shorter document called Gel and AGM batteries with the cycle life details.

By the way, we learned all this from a set of live aboard cruisers we spent 6 months with. Prior to that we were apparently abusing our batteries due to lack of our understanding. Frankly I'm surprised that the batteries are holding up as well as they are, since we only started to care for them properly in the second year of their life.
385 ubulukutu sail number GBR 3350L in Turkey and Greece with Mark and Catherine
Back to Top
High Time View Drop Down
Rear Admiral
Rear Admiral


Joined: 04 September 2012
Location: Portsmouth UK
Status: Offline
Points: 628
Post Options Post Options   Thanks (0) Thanks(0)   Quote High Time Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 12:23
Hi Mark

I assume the voltages are 'resting' i.e. the reading is taken after the batteries have been delivering zero current for an hour or so. Lower voltages will be seen while the batteries are delivering current, particularly if 2 fridges, instruments and autopilot are all working.


Edited by High Time - 30 May 2017 at 12:25
Roger

High Time (415 #038)
Back to Top
Mark&Catherine View Drop Down
Admiral
Admiral
Avatar

Joined: 18 January 2013
Location: Turkey
Status: Offline
Points: 1058
Post Options Post Options   Thanks (0) Thanks(0)   Quote Mark&Catherine Quote  Post ReplyReply Direct Link To This Post Posted: 30 May 2017 at 17:41
Yes you are correct the voltages apply when the batteries are resting or at least delivering low current, since we have some items on our 'never off' feed. I did try and look up the internal resistance of the AGMs but I can't find it anywhere. However I can calculate it using the difference between the voltage when our firidge is on and when off, since I know the current it takes. Generally I see a 5 % difference when the fridge is off on my battery monitor, so I watch for the 70% when it's on, 75 when it's off, this gives me some reassurance that I'm not discharging past 75%, probablybwith some contingency
385 ubulukutu sail number GBR 3350L in Turkey and Greece with Mark and Catherine
Back to Top
Manyata View Drop Down
Lieutenant Commander
Lieutenant Commander


Joined: 31 December 2013
Location: Lowestoft, UK
Status: Offline
Points: 52
Post Options Post Options   Thanks (0) Thanks(0)   Quote Manyata Quote  Post ReplyReply Direct Link To This Post Posted: 02 June 2017 at 12:58
Mark & Catherine & High Time

Thanks for the posts... much appreciated.

From your recent posts - it looks like my batteries might be 'past their best' would you agree ? After all - for them to show 12.2 (and that was resting when I switched everything off) after only having had 40AH drawn off them - from fully charged - they are ill - agreed ?

12.2v would appear to be about 50% discharged - yet 50% discharged would indicate about 165 AH used - no 40 AH - is my logic good ?

Regards

Tim
Back to Top
 Post Reply Post Reply Page  123 4>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 11.04
Copyright ©2001-2015 Web Wiz Ltd.

This page was generated in 0.048 seconds.

Links : www.hanseyachts.co.uk www.hanseyachts.com www.fjordboats.co.uk www.dehler.co.uk www.varianta.co.uk