lifepo batteries

Things 12V and 24V
Whimsical
Posts: 370
Joined: Sat Apr 28, 2007 8:01 pm
Location: Fremantle W.A.

Re: lifepo batteries

Post by Whimsical » Tue Nov 15, 2011 3:24 pm

08 62269682
Anybody wants to chat no problem i can call landlines for free so i will even call u if u want

Mike

Whimsical
Posts: 370
Joined: Sat Apr 28, 2007 8:01 pm
Location: Fremantle W.A.

Re: lifepo batteries

Post by Whimsical » Wed Jan 11, 2012 5:40 pm

Finally getting this order off the ground. Will be placing the order at the end of the month so if anybody else is interested contact me asap.

Chrisg
Posts: 141
Joined: Wed Feb 17, 2010 6:55 am
Location: Country Victoria

Re: lifepo batteries

Post by Chrisg » Sun Dec 22, 2013 6:07 pm

The building of Outback Dreamer is progressing very well to the point where the decision on the type of batteries to be used needs is required. AGM or Lithium :?: :?: :?:

The following link provided by another catamaran owner who replaced his lead batteries with Li gives a good summary - http://psyberspace.com.au/lithium.html
Chris & Michelle

Outback Dreamer - Sarah 23
http://www.outbackdreamer.com

Trev
Posts: 160
Joined: Thu Jan 15, 2009 2:56 am
Location: Moruya NSW

Re: lifepo batteries

Post by Trev » Mon Mar 17, 2014 12:03 pm

Does anyone know what has happened to EV Power in WA? their website no longer contains any contact details, have they gone out of business??
Trev

Chrisg
Posts: 141
Joined: Wed Feb 17, 2010 6:55 am
Location: Country Victoria

Re: lifepo batteries

Post by Chrisg » Thu Mar 20, 2014 7:20 pm

I just looked at the web site and all the contact details are there. The phone number is
(08) 9303 9040
Chris & Michelle

Outback Dreamer - Sarah 23
http://www.outbackdreamer.com

44c
Posts: 1148
Joined: Tue Aug 08, 2006 5:08 am
Location: Hervey Bay, Qld

Re: lifepo batteries

Post by 44c » Thu May 19, 2016 9:53 am

Well I finally bit the bullet and got Lithiums.

310 a/h Winston batteries at $2300 delivered.

They're certainly more expensive than AGM's or other lead acids, but if they last as long as claimed, should work out better in the long run. Just hope they last! (Replacing our AGM's with the same ones would have cost around $1600, and there were others I could have got for around $1200 delivered.)

AGM's were pretty stuffed after 6 years full-time liveaboard. Our friends from School's Out have some Lithiums that are about 6 years old and report they seem as good as new.

The other advantages are real enough - much lighter, more compact (mainly because you use about 1/2 the size of battery bank) and higher voltage.

Hope they last a good long time....

Finally
Posts: 223
Joined: Sat Jul 04, 2009 9:24 am
Location: Cairns

Re: lifepo batteries

Post by Finally » Thu May 19, 2016 12:19 pm

That's pretty good going to get 6 years out of a bank of AGM's - particularly for liveaboards where you are cycling the batteries every day.

It looks like the lithiums would need to last 1.5 times the normal life of AGM's to be cost effective. In your case they would need to last 9 years compared to the 6 years you got out of the AGM's.

Did you get a battery monitoring system with the pack? I suppose you also had fun locating your manual and delving into the solar controller setups to change the settings to lithium.

44c
Posts: 1148
Joined: Tue Aug 08, 2006 5:08 am
Location: Hervey Bay, Qld

Re: lifepo batteries

Post by 44c » Thu May 19, 2016 6:32 pm

Hi Dave, I thought 6 years was a bit short!

Yeah if the LiFePO4's last 9 years they're about cost equal.

I haven't bought a BMS, as the advice I got was that they're not really essential on 12 volt systems as long as lower voltage limits are observed.

The Outback Flexmax 80 is pretty easy to program, so upper voltage limit was easy to set, no absorbtion period, straight into float.

The Flexmax will also disconnect loads at a user adjustable voltage. I'll probably set it at about 12.2 volts or so. Just need to get a big relay.

All good so far!

mahnamahna
Posts: 580
Joined: Wed Aug 02, 2006 4:48 pm
Location: Gosford NSW

Re: lifepo batteries

Post by mahnamahna » Fri May 27, 2016 12:38 am

3.2v per cell is the nominal voltage of lifepo4 so 12.8 would be the ideal voltage wouldnt it? My understanding is they hold voltage until almost completely drained, under 5%.

Interesting ability of lifepo4 is their ability to hold a steady "shelf" voltage.

I have had mine sitting under the saloon seats for what must be approaching 3 years, could be more I just dont remember. They have never been connected to anything (each other or a charger) and all eight still hold exactly the same voltage of 3.19v. Not bad at all. I checked them again yesterday.

I plan to use these http://ev-power.com.au/webstore/ev-power-bms/cm090.html to keep the cells balanced, $15 each is quite cheap and worth it for the peace of mind.

44c
Posts: 1148
Joined: Tue Aug 08, 2006 5:08 am
Location: Hervey Bay, Qld

Re: lifepo batteries

Post by 44c » Fri May 27, 2016 8:35 am

I believe the cell modules need to be connected to a BMS, which vary in price depending on the number of cells. However from experience of some friends, failures of cell modules seem to be far more frequent that failures of cells.

According the EV Works, a 12 volt system is unlikely to overdischarge a single cell to the point of damaging it without the overall voltage dropping very low, well below 12 volts.

"At the other end of the scale, over-discharging can also cause cell damage. The BMS must disconnect the load if any cells are approaching empty (less than 2.5V). Cells may suffer mild damage below 2.0V, but are usually recoverable. However, cells which get driven to negative voltages are damaged beyond recovery.

On 12v batteries the use of a low voltage cutoff takes the place of the BMS by preventing the overall battery voltage going under 11.5v no cell damage should occur. On the other end charging to no more than 14.2v no cell should be overcharged."

http://www.evworks.com.au/page/technica ... hium-batt/

I feel that 12.2 allows transient voltage drops due to loads, but still leaves a good safety margin.

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