New Lithium-Ion Batteries

[Catalysis]

Another lithium phoshate supplier - lower cost - has anyone used them?

www.Lithiumion-batteries.com

Also has has anyone have experience in charging 24v lithium power pack ?

I'm considering leaving my 12v house system intact and charging a 24v power pack (dedicated to a thruster) via a 12v to 24v isolation transformer.

Paul

[foggysail]

Originally Posted by Catalysis

Another lithium phoshate supplier - lower cost - has anyone used them?

www.Lithiumion-batteries.com

Also has has anyone have experience in charging 24v lithium power pack ?

I'm considering leaving my 12v house system intact and charging a 24v power pack (dedicated to a thruster) via a 12v to 24v isolation transformer.

Paul

HOLY SMOKEY ANDY!!! May I ask, lower cost than what?

Foggy

[FlyingCloud1937]

Originally Posted by Catalysis

Copying my post from Lithium Ion string: Appreciate your thoughts

Re: New Lithium-Ion Batteries
Another lithium phoshate supplier - has anyone used them?


Another lithium phoshate supplier - lower cost - has anyone used them?

www.Lithiumion-batteries.com

Also has has anyone have experience in charging 24v lithium power pack ?

I'm considering leaving my 12v house system intact and charging a 24v power pack (dedicated to a thruster) via a 12v to 24v isolation transformer.

Paul

Hi Paul,

I stopped being an early adopter to new technology, for one simple reason...costs. Early adopters are the funder's of research and development with little to gain and more to lose.

The only reason I might become an early adopter of new-technology/under-developed technology. Is if I couldn't fulfill the current need with existing technology.

You pay way to much, and most likely never amortize before failure or replacement with the newest latest and greatest. Certainly we have seen this time and time again, manufacture claims that don't meet reality. All we need do is look at the history of TV's, computers, personal mobile devises.

I have found it better to wait until the manufacturing cycle drives the price point to match an equilibrium with supply/demand.

If you have a need then maybe.

Lloyd

[Sparohok]

Originally Posted by Catalysis

I'm considering leaving my 12v house system intact and charging a 24v power pack (dedicated to a thruster) via a 12v to 24v isolation transformer.

Be aware - you need a DC to DC converter, not an isolation transformer. Transformers only work with AC. Batteries are DC.

Martin

[Catalysis]

Martin:
Thanks for the clarification on terminology. My question is will the DC to DC converter provide the desired isolation of the Lithium ion battery pack from the lead acid batteries so that I can keep my charging systems as is?
Paul

[T1 Terry]

I've been using a LifeP04 battery pack for around 5mths now, can't believe just how different these batteries are. Don't be caught out by those determined to fleece the unsuspecting of their hard earned $$ the price these people are charging is ridiculous.
Li isn't cheap but it's not that dear. Winston Batteries I believe have set up a distribution system throughout the US and various parts of the world, there are at least 3 places in Aust to buy them and we are usually the last place on earth to get anything of any use :lol:
The easiest and safest format cells to use are prismatic cells, plastic blocks that look just like the batteries we all know. Each cell can be bought individually in a heap of different Ahr sizes but each cell is 3.2v so it take 4 cells to build a 12v battery. I believe the price in the US is $1.20Ah in a 3.2v cell so 4 cells at 100Ah would be $480. Not that outrageous if compared to Lifeline or Rolls AGM and this is the quality level to be doing the comparison at, not car cranking batteries.
These cells don't fail under vibration, charge very fast and hold their terminal voltage high right to the very end. A 4 cell 12v configured battery will hold 13v plus across the terminals under a reasonable size load. These batteries don't have a problem with not being immediately recharged or every really need to fully charged actually, hey can be topped up when it suits the operator and the rough figure of 80% DoD will return better than 3,000 cycles. Keep in mind that's 3,000 times from 100% full to 80% DoD, not just cycles, stay inside the 2 extremes and they last much longer than that. They use this technology in space missions and satellites, they have been well and truely tested to prove their reliability.

Don't caught out by the nonsense that the batteries will be destroyed if an expensive BMS system isn't used, in a 4 cell battery that is pure nonsense and only put out by the people who want to sell you their latest and greatest BMS unit. Simple periodic checks and a minimal amount of maintenance and they are happy.

I have carried out a lot of testing on these batteries and I have built up a reasonable knowledge base regarding using these batteries as both house batteries and serious energy supply batteries. I'm happy to share it with anyone who is genuinely interested, these batteries will simple amaze you with their capabilities.
Here is a little taster. This test is using an inverter to power a 240vac coffee percolator, the 2 batteries are a 100Ah gel cell and a 90Ah 12v Winston LiFeP04 lithium battery made up from 4 cells linked together.
Usual disclaimer, I don't sell anything, have no financial interest in any company, just hate seeing people ripped off by these B/S companies.

T1 Terry

[Jorma]

Thanks T1 Terry

for shearing the information and pointing out the difference between LiFePO4 and other types of lithium batteries - especially on price. LiFePO4 is a realistic choice today.

If some of you are not yet familiar with LiFePO4, there are two main threads on this topic: http://www.cruisersforum.com/forums/...art-36530.html and
http://www.cruisersforum.com/forums/...nks-65069.html

The only problem I have had so far with the LiFePO4 is protecting the batteries from low voltage - it is a real threat as they will die at once (?) if they are ever run to 100% DOD ie empty. That is why I have not updated to LiFePO4 yet. It gets tricky with these BS-systems.

So - how do you disconnect the batteries before they reach low voltage and how do you take into consideration that some heavy loads (like my espresso machine ) will bring the voltage down although it is not 100% DoD?

[Sparohok]

Originally Posted by Catalysis

Martin:
Thanks for the clarification on terminology. My question is will the DC to DC converter provide the desired isolation of the Lithium ion battery pack from the lead acid batteries so that I can keep my charging systems as is?

Yes it will. The DC to DC converter will trickle charge your 24 volt thruster bank from the house bank. A 24 volt @ 10 amp DC-DC converter will cost you a few hundred bucks. They are about 90% efficient. Smaller ones are cheaper but it could take a heck of a long time to charge your 24 volt bank.

Martin

[T1 Terry]

Originally Posted by Jorma

Thanks T1 Terry

for shearing the information and pointing out the difference between LiFePO4 and other types of lithium batteries - especially on price. LiFePO4 is a realistic choice today.

If some of you are not yet familiar with LiFePO4, there are two main threads on this topic: http://www.cruisersforum.com/forums/...art-36530.html and
http://www.cruisersforum.com/forums/...nks-65069.html

The only problem I have had so far with the LiFePO4 is protecting the batteries from low voltage - it is a real threat as they will die at once (?) if they are ever run to 100% DOD ie empty. That is why I have not updated to LiFePO4 yet. It gets tricky with these BS-systems.

So - how do you disconnect the batteries before they reach low voltage and how do you take into consideration that some heavy loads (like my espresso machine ) will bring the voltage down although it is not 100% DoD?

The 100% Dod doesn't kill them, having a cells voltage dragged to zero volts and held there kills them. You may not get the 3,000 plus cycle life if you constantly drag them down to 100% DoD but it doesn't kill them dead.
I use a Plasmatronic PL20 as my solar control and battery monitor, it has a State of Charge (SOC) function built in and can be set to turn off a relay at a preset SOC so mine is set to 20%. I've never reached i yet to see if it works, guess I should one day just to be sure.
There is are a few different units available that monitor cell voltage, I use a Junsi CELL log 8 made by SHENZHEN JUNSI ELECTRONIC CO.,LTD, I bought mine on line from Hobby King for about AU$28, mine is a logger as well as a monitor so I can down load the info to the computer and make those fancy charts like the ones I posted if I want to, just makes it easy for me to do the testing. These Junsi units are also available without the logger function about AU$14. They all will give a reading of each cell voltage, total battery voltage and the drift between cells. Each one of the these measurements has an adjustable high and low alarm set point that sounds an annoying beeper if any get exceeded but also there is an external alarm port that can either turn a relay off or set of a loader alarm or what ever suits best. If you are only going to use the batteries as house batteries 3v per cell will see then safe but if they are gong to be used for high load like motor driving then 2.5v will allow for cell voltage sag under high load as the cells get close to the 80% DoD state.
Did that help or just confuse things, I tend to ramble a bit If any of it didn't make sense I'm happy to try and explain it better or post links to suppliers if that's allowed here.

T1 Terry
EDIT: Don't know what happened there, tried to fix my poor spelling and typing and the font went huge

[Therapy]

Originally Posted by T1 Terry

I've been using a LifeP04 battery pack for around 5mths now, can't believe just how different these batteries are.
T1 Terry

Thanks for that info.

[bill good]

Hi all, One major difference is that after about 7 yrs about 30% capacity is lost due to chemistry of the materials used in LIFEPO4 but after this initial loss they will still continue to be used with this lesser capacity for a further period. The loss of capacity is slower in the next period. This does not happen with lead acid. It appears the LIFEPO4 will be the choice for the large scale introduction of the electric car. The supply & demand will be the driving force in the pricing point. So (1) try for 30% larger capacity (2) understand the technical data for cell life.

Regards Bill

[T1 Terry]

Do you have a link for more info regarding using these cells for house batteries Bill? Always keen for more info.

T1 Terry

[witzgall]

For anyone that is interested, I have four new 200ah LIFEpo4 cells for sale - check the classifieds here...

Chris

[Jorma]

Originally Posted by T1 Terry

The 100% Dod doesn't kill them, having a cells voltage dragged to zero volts and held there kills them. You may not get the 3,000 plus cycle life if you constantly drag them down to 100% DoD but it doesn't kill them dead.
I use a Plasmatronic PL20 as my solar control and battery monitor, it has a State of Charge (SOC) function built in and can be set to turn off a relay at a preset SOC so mine is set to 20%. I've never reached i yet to see if it works, guess I should one day just to be sure.
There is are a few different units available that monitor cell voltage, I use a Junsi CELL log 8 made by SHENZHEN JUNSI ELECTRONIC CO.,LTD, I bought mine on line from Hobby King for about AU$28, mine is a logger as well as a monitor so I can down load the info to the computer and make those fancy charts like the ones I posted if I want to, just makes it easy for me to do the testing. These Junsi units are also available without the logger function about AU$14. They all will give a reading of each cell voltage, total battery voltage and the drift between cells. Each one of the these measurements has an adjustable high and low alarm set point that sounds an annoying beeper if any get exceeded but also there is an external alarm port that can either turn a relay off or set of a loader alarm or what ever suits best. If you are only going to use the batteries as house batteries 3v per cell will see then safe but if they are gong to be used for high load like motor driving then 2.5v will allow for cell voltage sag under high load as the cells get close to the 80% DoD state.
Did that help or just confuse things, I tend to ramble a bit If any of it didn't make sense I'm happy to try and explain it better or post links to suppliers if that's allowed here.

T1 Terry
EDIT: Don't know what happened there, tried to fix my poor spelling and typing and the font went huge

Thanks T1 Terry for your info - learning a lot.

I have looked for max charging currents of LiFePO4 batteries. I see figures from 0.4C to 3 C. What is your view- how high can the charging current be for repeated charging without the cycle life coming down more than 20% ?

As you can see, I am looking for maximum “reasonable safe” charging current.

Jorma

[T1 Terry]

Hi Jorma,
0.5C is the rate the factory does the cycle life testing, 1C causes very little increase in terminal voltage, 3C starts to push the boundaries, I have seen them charge at 5C but close attention to cell terminal voltage become essential once you start to fast charge at those rates.
The critical thing is to keep individual cell voltages below 3.6v, 3.5v is ideal but 3.6v is safe as long as that voltage isn't maintained for hrs on end.
Electrolyte temperature is the killer, if it gets over 60degC parts of the electrolyte separate and begin coating the anode if charging and cathode if discharging.(Think I got that the right way around) The electrolyte gets heated if more lithium ions are trying to be forced through it than can be absorbed by either the anode or cathode, depending if charging or discharging. 4v per cell absolute max for very short periods when charging and 1v for very short periods discharging, less than a minute, the electrolyte will heat rapidly.
Specifying an exact max C rate is very difficult because it depends on how the cells have ben treated, once any coating has occurred the surface area for absorption is reduced, this process is not reversible. If you were to stick religiously to the 0.5C in either charge or discharge, stay between 70% DoD and 5% DoD (30% SOC and 95% SOC) you would probably be deciding which kid to leave them to in your will, eventually their capacity reduces but it is so slow after the 70% mark it would be hardly noticable. The Winston cells are rated to 5,000 cycles to 70% DoD, discharged to 70% and the recharged to 100% every day for close to 14 yrs.

T1 Terry