LiFePO4 Batteries - Okay Tear Me Apart ;-)

[electric1]

Originally Posted by gbanker

can this new battery accept higher charging rates? does this new technology require that we upgrade our battery chargers or alternators to make full use of it benefits? if these batteries can accept higher charging rates and the charging methods are not upgraded, is there any benefit in terms of reduced charging times?

There is no single answer, since you have a few options. This all depends on the size of your house bank and your power needs.

- if your current Lead Acid bank meets your power needs, then you can get LFP bank of half the size and it will still meet your needs and you can use the same charger, but charge time will be reduced since there is no Puekert loss anymore.

- if you get LFP bank of the same nominal size as your current Lead Acid bank, then you will have twice as much usage time at the same power level, so you won't have to charge as often, but charge time will remain the same, unless you also upgrade your charger/alternator to reduce charge time and increase efficiency. You would also be able to increase your power needs with this option.

LFP just makes everything more flexible and easier to calculate and priovides much larger range of charge/discharge options.

[JHJensen]

Originally Posted by witzgall

I built a 24v, 40ah battery from Sky Energy LIFEPO4 cells this summer. The cells came from EV Components, and I sourced the charger and BMS from a Hong Kong supplier directly. It is powering our Torqueedo dingy motor.

So far, so good. The pack weighs 26 lbs, in one of the orange waterproof boxes. Compare that with a 12v, 80ah Lead Acid battery, at what, perhaps 70lbs?

Chris

Chris I would like to know more about that pack you put together...I am thinking about the same thing for a kayak for someone who is disabled. That Torqueedo is a nice piece of gear, well made too

[LiFeTech Energy]

Originally Posted by gbanker

can this new battery accept higher charging rates? does this new technology require that we upgrade our battery chargers or alternators to make full use of it benefits? if these batteries can accept higher charging rates and the charging methods are not upgraded, is there any benefit in terms of reduced charging times?

Much, much faster charging compared to lead acid/AGM/gel batteries.
LiFePO4 batteries must be able to be charged at a far higher rate than lead acid batteries since they are designed primarily for the electric vehicle market. For example the specification for charging of LiFeTech LiFePO4 batteries is that a completely discharged battery can be almost fully recharged (to greater than 90% capacity) in 15 minutes.
Try doing that with a lead battery and see how long it lasts!

Yes, alternators and solar/wind regulators can all be used with LiFePO4 batteries but where possible programming/regulator settings should be slightly modified so as to optimise them for charging lithium batteries.
For example I have recently supplied lithium batteries to the owner of a boat who has changed over from his AGM batteries to LiFePO4 batteries for house power. The owner decided to buy the lithium batteries because he wants to increase the efficiency of his battery/electrical systems as well as substantially reduce the total battery weight. The owner of the boat already has a Morningstar Solar MPPT charge regulator and I have been discussing with the owner (as well as the technical staff at Morningstar) changes to the programming settings. Basically the only changes which need to be made to the Morningstar regulator program is to change the end of charge voltage from 14.4V (for lead acid) to 14.6V (for LiFePO4) and to disable the equalization function which is not required for lithium batteries. The technical staff I have been in communication with from Morningstar have been most helpful indeed and very interested in learning about the lithium technology and it looks as if they will be writing a dedicated LiFePO4 charging program so their regulators can be used with LiFePO4 batteries.

By the way you asked if this "new" battery accept higher charging rates.
LiFePO4 batteries aren't exactly "new" considering they were invented nearly 20 years ago.

[LiFeTech Energy]

Chris I would like to know more about that pack you put together...I am thinking about the same thing for a kayak for someone who is disabled. That Torqueedo is a nice piece of gear, well made too

Yes, the Torqueedo motors are by far the most efficient electric outboards on the market. There is a great video of the Kayak motor on the Torqeedo website.
Many of my electric boat projects which I supply lithium batteries are powered by Torqeedo motors.
We will be building two purely electric patrol boats which will use two of the Torqeedo Cruise4 motors (currently the most powerful motor Torqeedo manufacture). These patrol boats will have 1 hour fast charging at the marina.
Due to the efficiency of the Torqeedo electric boat motors combined with the efficiency of the LiFePO4 batteries I am supplying makes this project possible.

The owners of these boats have decided to replace their current diesel powered boats with electric patrol boats since their calculations show they will save around $35,000 per year per boat on cost savings in not having to buy diesel fuel as well as zero diesel engine maintenance costs.

I have always found Claude Desjardins from Torqeedo to be most helpful and for any questions and for advice about your kayak project you can always contact Claude at- Claude@torqeedoaustralia.com

Some of the worldwide Torqueedo distributors are more knowledgeable and helpful than others and I would say Claude is definitely one of the best.

[LiFeTech Energy]

Hi John,

Thanks for your private message. I have no objection at all about posting my reply on the open forum. I am all about sharing information where ever possible so others can learn and gain ideas and thereby provide the confidence in others to try out new electric motor and battery technologies. I am fortunate to be at the forefront of these technologies (as far as lithium batteries are concerned) so I am more than happy to share my knowledge with others wherever possible.
So for the benefit of others first your message-


Thank you for your response. I went through the Torqeedo website. I had seen their motors before including the kayak model. Just had not looked at them. Thanks for the heads up. I can see their products in several projects we have on the boards.

Demand for electric power on vessels of all sizes in doing nothing but getting bigger.

I would love to see some photographs of your patrol boats. A very interesting concept. Have a few questions like how big and how are they used? Where are you located?

I sent you the private message as I did not want to ask questions you might not want to have in the public forum.

I look forward to more contact with you.

Thanks again,

John H. Jensen
Jensen Maritime Group

John the electric patrol boats are in the planning stages and the marine architects have the drawings so there are no photos as yet since it is expected construction will start on the first boat in the next couple of months after the everything has been finalised. There have been ongoing changes to the design of the boats but basically they will be small twin engine electric patrol boats 6m (20ft) in length for security patrols at Sanctuary Cove here in Australia. They will be powered by two Torqeedo Cruise 4 (48V 4000W) electric boat motors. The motors will be supplied power from 4x 48V 45Ah LiFeTech LiFePO4 batteries (model XPS2E-048045) connected in parallel so the total battery capacity per boat will be 48V 180Ah. The batteries will be fast charged from shore power and we are looking at installing the fastest possible charger which is dependent on the power supply available. If the power is available we are looking at installing a 48V 8kW LiFePO4 charger so we can recharge in about 1 hour.
Claude from Torqeedo has calculated the patrolling time per charge will be around 6-8 hours depending on the motor power level. The Torqeedo motors are incredibly efficient and with low power settings a comfortable cruising speed of 4-5 knots will allow all day patrolling. Of course if the opportunity arises to return to base for a lunch break etc. fast charging will allow the batteries to be topped up to capacity very quickly and so patrolling can resume again with a fully charged battery.

For anyone coming to Australia next month I would urge you to visit the Sanctuary Cove International Boat Show. The Sanctuary Cove Boat Show is the largest and most prestigious boat show in Australia and one of the largest trade boat shows in the Southern Hemisphere. A list of exhibiting companies at the boat show is on the boat show website here- Sanctuary Cove International Boat Show - 2010 Show

I personally am not exhibiting at the boatshow but will be attending and assisting at the Torqeedo stand. I am supplying some LiFePO4 batteries to Torqeedo which will power some of the motors on display as well as for the first time at this year's boat show visitors will be able to be taken for a cruise in a couple of small electric boats which will be on display at the show. This should provide an insight for many people into the benefits of fume free, peace and quiet electric boating (which many people who have tried this for the first time remark how relaxing it is).

If anyone is coming to the boat show be sure to come and say hi! I will be there each day of the show but will also be visiting my largest electric boat project to date "Roow With A View" which is a well known 55ft racing catamaran which is normally based in the Great Barrier Reef. RWAV is less than an hours drive from Sanctuary Cove and is in the final stages of a full electric conversion.
Rather than post photos and information here I think it is best to start a new thread. I am sure forum readers will find this project most interesting. There are many single and twin Torqeedo powered electric boats but this is the only e-boat in Australia which will have triple Torqeedo motors fitted.

[bill good]

I will sail down weather permitting!! May see you there.

[LiFeTech Energy]

Will look forward to seeing you Bill!

[JHJensen]

Lifetech,
Thanks much for your response and the information about your patrol boats they sound like a very interesting project. I could see the same being used here in some of our own harbors and protected waters. We are about sharing as well and encourage the same but had the experience of some folks wanting questions in private first and then opening discusions on the boards as they were so inclined.

The technology of using lithium batteries opens up all kinds of new applications much the way Gels and AGMs have in the last ten years. Wish I could come down and see some of your projects.

John

[LiFeTech Energy]

Originally Posted by JHJensen

Lifetech,
Thanks much for your response and the information about your patrol boats they sound like a very interesting project. I could see the same being used here in some of our own harbors and protected waters. We are about sharing as well and encourage the same but had the experience of some folks wanting questions in private first and then opening discusions on the boards as they were so inclined.

The technology of using lithium batteries opens up all kinds of new applications much the way Gels and AGMs have in the last ten years. Wish I could come down and see some of your projects.

John

John, there are plenty of articles to read about regarding electric boating and the various projects which are underway.
There is some helpful information on the EBAA website and in particular you might like to read some of the featured articles on the website-
About the EBAA | Electric Boat Association of Australia

Happy reading and researching!

[downunder]

I believe this is the patrol project being referred.

Design by Grainger designs. links below.

Powerblade
Grainger Designs For Custom Catamaran Design and Trimaran Design For Cruising or Racing

or Twinblade
Grainger Designs For Custom Catamaran Design and Trimaran Design For Cruising or Racing

[LiFeTech Energy]

Thanks for that Downunder! I wasn't aware of those pictures.
Grainger Designs was one of the companies which submitted a tender to design and build the electric patrol boats. The latest news I have is that Sanctuary Cove are going with another design/company though the boats look quite similar.
The final design will be approved at the next board meeting.

As mentioned on the Grainger website the Torqueedo motors are incredibly efficient with an overall efficiency (delivered at the prop) of 45% to more than 50% depending on motor model).
Not bad when you consider the efficiency of traditional electric trolling type boat motors eg. Minn Kota, Motorguide, etc. is no more than 10%.
It is this high efficiency which allows all day cruising/patrolling on a single battery charge when lithium batteries are used.

[JHJensen]

Originally Posted by downunder

I believe this is the patrol project being referred.

Design by Grainger designs. links below.

Powerblade
Grainger Designs For Custom Catamaran Design and Trimaran Design For Cruising or Racing

or Twinblade
Grainger Designs For Custom Catamaran Design and Trimaran Design For Cruising or Racing

Originally Posted by LiFeTech Energy

Thanks for that Downunder! I wasn't aware of those pictures.
Grainger Designs was one of the companies which submitted a tender to design and build the electric patrol boats. The latest news I have is that Sanctuary Cove are going with another design/company though the boats look quite similar.
The final design will be approved at the next board meeting.

As mentioned on the Grainger website the Torqueedo motors are incredibly efficient with an overall efficiency (delivered at the prop) of 45% to more than 50% depending on motor model).
Not bad when you consider the efficiency of traditional electric trolling type boat motors eg. Minn Kota, Motorguide, etc. is no more than 10%.
It is this high efficiency which allows all day cruising/patrolling on a single battery charge when lithium batteries are used.

I had an idea about these vessels but the pictures give one a much clearer picture of the design and what to look for in this type of vessel.

Lifetech, Your comments on the "other" electric motors low efficiency available are so true and one of the reasons why I did not consider them.

Thank you both for expanding our knowledge base!

[Isara]

600Ah@24v built with 16 ThunderSky LiFePO4 (2 x 8):
35"x15"x12" -- 6300cu-in (no battery boxes required.)
337lbs (16x21lbs)
>8000 cycles (@50%)
$5808 ($330x16 = $5280, +10%)

For our solar powered boat project, I've been told we need to create a 30-50kw battery bank. Just to make sure I'm doing the math right (amps x volts = watts), the above example is about 14kw. So we would need (roughly) 3x the above setup, correct? Is there anything else to consider (BMS, etc.) when creating a battery bank that big? Is there any software/hardware that can be used to monitor LiFeP04 battery performance and health?

Thanks.

[bill good]

My cat at 5t will do 5.5kts still conditions for 2.5HP (actual) at each shaft. If the solar panels are fixed in a flat plane best you can expect is 50% ie 200watt panels will give 100watts average over the day.

[OceanPlanet]

Regarding high-efficiency MPPT solar charge controllers, Genasun already makes them for both LiFePO4 (LFP) and lead/gel/agm.

If you get your own LFP cells like the large-format Thundersky, you might consider getting the BMS from Genasun. Their BMS is designed specifically for marine use, as opposed to an EV-based BMS. One example of their marine-based features is a built-in field current cutoff switch to protect the alternator(s) in the case of an HVC (charging relay cutoff). The balancing is full-time so the need for "manual" balancing is virtually eliminated.

The BMS can be programmed by Genasun for different LFP cells voltage, for instance either Sky Energy or Thundersky.

Of course the higher level of protection costs more $. For those sailors that can carefully monitor the pack and cell voltages and do the occasional balancing charge, then you could possibly get by with a less expensive BMS. One example is the shunting boards as on the RaceCell LFP batteries, that provide balancing (and some HV protection) at the top of the charge cycle. With this type of system one definitely has to be careful to protect your cells but you save a lot of $.

Different BMS's for different folks!