A poll Happy with LiFe (PO4)?

[senormechanico]

That's comforting to think about.
My new "closeout" 700 aH cells from Balqon have resting voltages around 3.37 volts.
I was wondering if I'd over cooked them.

[CAELESTIS]

BK? @#$%!! You guys were just about to set the hook on me with these batteries.

What Winston battery has a similar footprint to a golfcart (UHC2500 Interstate)? I currently have a 550a @24v bank, with a 140a @24v Leece Neville alternator, and in a week, 480w of Sanyo panels. Honda 2000i for back up.

Please advise.

[deckofficer]

Originally Posted by CAELESTIS

BK? @#$%!! You guys were just about to set the hook on me with these batteries.

What Winston battery has a similar footprint to a golfcart (UHC2500 Interstate)? I currently have a 550a @24v bank, with a 140a @24v Leece Neville alternator, and in a week, 480w of Sanyo panels. Honda 2000i for back up.

Please advise.

Footprint for fit? Typical golf cart battery 10.3" X 7.1" Height 11"

My (4) 100 a-hr Winston cells 10.0" X 7.0" Height 8.75"

You must have used (8) 6 volt golf cart batteries. (24) of the 100 a-hr cells in a series/parallel would give 400 a-hr at a weight of 180 lbs.

[CAELESTIS]

Yes, 8 batteries.

What model battery is the one you mentioned?

[deckofficer]

Originally Posted by CAELESTIS

Yes, 8 batteries.

What model battery is the one you mentioned?

I have the Winston 100 a-hr cells, 2 packs of 4 cells in series.

If you have open room and don't need to match a golf cart battery's footprint I would go with a series string of cells, in your case for 24 volts (8) of the 300 a-hr would give you more usable a-hr than your 550 a-hr LA pack.

[T1 Terry]

Originally Posted by CAELESTIS

Yes, 8 batteries.

What model battery is the one you mentioned?

Just a note here, you can not connect the Li batteries up as 8 X 6v batteries, you need to link the cells up so you build 8 x 3.2v batteries to form one big capacity 24v battery.
So, using Bob's suggestion of 4 x 100Ah cells in each group connected with all the positives together and all the negatives together, join 8 of these groups together positive of one to negative of the next and you will have a 400Ah x 24v battery ready for charging.

T1 Terry

[T1 Terry]

Originally Posted by deckofficer

T1 Terry,

Cycles 1~40 about 1/2 were as you put it, "a thrashing." Cycles 41~current have been 2 hours at 40 amps or 80 amps pulled from the 100 a-hr cells. Resting voltage after these 80 amp draws has been 3.25 VPC or 13.0 volt pack voltage, so no longer thrashing.

My apologies Bob, I forgot you had weakened with the christmas spirit and decided to show those poor cells some mercy :lol:
Do you see much voltage drop now between the beginning and end of the load test?

Some of the charging rates and load rates published on the other thread for some of the other manufacturers are either very conservative or they have very little faith in their product

T1 Terry

[deckofficer]

T1 Terry

Coming off the charger
3.56, 3.51, 3.55, 3.54

Coming off a 40 amp load for two hours
3.26, 3.25, 3.25, 3.25

[deckofficer]

bigwhyte, scottyo have voted that Li was a mistake for them. I PM'ed bigwhyte last week and no response and scottyo just voted today.

Come on guys, if you have had a bad experience with Li, please share what happened.

[deckofficer]

The two "No" votes are from people that have never owned LiFePO4 cells. A reminder, this poll is for folks that have owned and used these cells, not opinions. So, we are still at 100% satisfaction and when a mod gets the chance, please remove the two "No" votes. Thanks.

[Dashby]

Great post Flying Cloud, agree completely with sentiment and I have had that bad experience with supplier/manufacturer saying cell balancing NOT required.
But after putting in a new set of batteries with full BMS and top balancing have 12 months of charter experience use that says it can be good experience if installed correctly with multiple cut off relays and we have two BMS systems.

Regards

Doug

[deckofficer]

The 3rd "No" vote came from a radio controlled model boat user, not a full size boat. For our proposes, still 100% satisfaction.

[d design]

When using LiFes it is very important that all yor coneections are perfect and crossion free. A ever so slightly bad connection can confuse a battery management system and could cause overcharging and potentialy ruining your expensive batteries. Dont get me wrong it has happened to me.

[deckofficer]

Originally Posted by d design

When using LiFes it is very important that all yor coneections are perfect and crossion free. A ever so slightly bad connection can confuse a battery management system and could cause overcharging and potentialy ruining your expensive batteries. Dont get me wrong it has happened to me.

But this was on a small scale RC battery, right? Not the large 100~1000 a-hr cells we use as house and/or propulsion banks.

[d design]

Originally Posted by deckofficer

But this was on a small scale RC battery, right? Not the large 100~1000 a-hr cells we use as house and/or propulsion banks.

I dont see why it would be different on a large bank. The marine environment is extremly corosive and good maintanance to your battery connections should give you 100% satisfaction. I wont post any more on this thread as its about peoples experiences with these batteries and not someone ranting on about them.