LiFePO4 Batteries: Discussion Thread for Those Using Them as House Banks

[downunder]

This looks like same logger.

cell logger connections - YouTube

[downunder]

Originally Posted by Lagoon4us

Fairly sure these are or are similar to the JUNSIE that Terry advocates, i think they are cheaper on Ebay and as Terry says you need to get the connector plugs when purchasing..

Cheers

Seems it is the same Junsie logger anyway.

[goboatingnow]

Originally Posted by daddle

Monitoring individual cells with a voltmeter? Or is there an hands-free method of accomplishing this.

My point is trying to determine if this technology remains in the fanboy stage or is ready for cruisers that have better things to do than monitor batteries.

Li is mainstream technology, well understood by those building systems around them. Li simply hasnt made it into boat, primarily because of price and lack of knowledge. Li is actually way more robust then LA,

Because High Voltage is particularly damaging to LI. It is wise to measure the individual cells in a series string. This can be done with a 30 buck cell monitor. Thats all really.

Dave

[hellosailor]

Well, if a "small" Group24 car battery can weigh 40-50#, and switching to Lithium-whatever can cut that in half, saving 20-25# in weight on the vehicle...

Someone has probably already done the math to figure out the extra cost of the battery, the charge system, the monitor, the warranty issues, all versus the fact that knocking out 20# in one shot will increase the mpg rating and they are all under federal mandate to make big mpg changes. In theory.

So that's a good point, lithium should start showing up in cars for SLI batteries Real Damn Soon unless the carmakers are finding it grossly unsuitable for some reason. Fastest in "performance" applications where the weight counts most, but in everything as they run out of ways to meet mpg changes.

[goboatingnow]

sorry for the cut and paste

2013 outlook for EVs with Li tech

"Nissan’s (TYO: 7201) 2013 Leaf will be equipped with Lithium-ion batteries developed and manufactured at the company’s new cell-manufacturing facility in Tennessee, Resource Investing News reports. The facility is the biggest automotive-scale Li-ion battery plant in the U.S. and represents a $1.7 billion investment. Its development involved hefty incentives and funding by the Department of Energy’s Advanced Technology Vehicles Manufacturing Loan Program.
The facility has a production capacity of 200,000 EVs yearly. As for the Leaf, it has sold around 46,000 units in two years on the market; some 18,000 of those sold within the U.S. Nissan intends to unveil around 15 new hybrid models by 2016, and the 2013 Leaf will likely boast a longer range than the 2012 model’s EPA-rated 73 miles.
Meanwhile, General Electric (NYSE: GE) is about to come out with the 2014 Cadillac ELR, a luxury coupe featuring a PHEV drivetrain. It is expected to share similarities with the Chevy Volt plug-in sedan, complete with Li-ion battery and four-cylinder engine.
Volkswagen (ETR: VOW) is investing $9.13 billion a year on electric vehicles, and we should expect to see PHEV variants of the Porsche Panamera, Cayenne SUV, 918 Spyder, and the Golf, Passat, and Audi Q7 SUV.
Ford (NYSE: F) is focusing heavily on EVs too, devoting some $135 million toward the Fusion Hybrid, Fusion Energy PHEV, C-MAX hybrid, C-MAX Energi PHEV, and the Focus Electric. All of these feature the latest in Li-ion battery technology, and all should come out over 2013. The Fusion Hybrid is EPA-rated for 47 mpg, and was nominated for Green Car Reports’ Best Car to Buy for 2013.
Finally, BMW (ETR: BMW)—a little late to the game—hopes to bring out its first all-electric offering, the i3 coupe, in late 2013. It is expected to feature a 125 kW/250 Nm electric motor, single-speed transmission, and a 160-kilometer range.

[hellosailor]

BMW and Toyota had announced a joint EV progam last year, but since then Toyota has alos radically cut back their EV plans as a whole, having second thoughts about wether they really can deploy in large numbers.

Now, if you could pull into a fuel station, stop for a cup of coffee and a newspaper, and get your car back with at least 1/2 charge in ten minutes or less, that'd be a game changer. Eight hours...we're gonna need a bigger buffet table.

[goboatingnow]

ultimately the only way EVs will work will be replaceable battery technology. Ie you pull in to a refill station and a automated unit removes the battery pack and replaces it with a charged one, hey presto.

Of course well find then that EV power is just as expensive as gasoline "plus ça change, plus c'est la même chose"

[goboatingnow]

Just as a comment, Any Bench supply that has overvoltage protection ( and most do) can be used to test charge Li cells. Just put a multimeter on the cell as a monitor, dont trust the display on the power supply.

Dave

[hellosailor]

"replaceable battery technology"
That's been done already overseas for a couple of years. But unless you can get all the car makers to switch to D cells...they're putting batteries solidly in the middle, for protection against impact, and they ain't gonna play swapee-swapee.

[mcarling]

Originally Posted by hellosailor

Well, if a "small" Group24 car battery can weigh 40-50#, and switching to Lithium-whatever can cut that in half, saving 20-25# in weight on the vehicle...

Someone has probably already done the math to figure out the extra cost of the battery, the charge system, the monitor, the warranty issues, all versus the fact that knocking out 20# in one shot will increase the mpg rating and they are all under federal mandate to make big mpg changes. In theory.

So that's a good point, lithium should start showing up in cars for SLI batteries Real Damn Soon unless the carmakers are finding it grossly unsuitable for some reason. Fastest in "performance" applications where the weight counts most, but in everything as they run out of ways to meet mpg changes.

Yes, that's my thinking. What I cannot guess is whether or not they will package charge management electronics inside the battery case. If they do, then the boating solution would probably be to put 12.8V lithium phosphate automotive batteries in parallel, much as we do now with lead acid batteries.

[deckofficer]

Tesla Model S is Motor Trends car of the year. 80 kw fast charge will give 160 miles in 30 minutes, range on a full charge is 300 miles.

2013 Motor Trend Car of the Year: Tesla Model S - Motor Trend

[hellosailor]

"As Tesla says, stops on long drives often take that long [30 minutes after every 2-1/2 hours] anyway, if you use the bathroom, stretch, and grab a snack."

Dunno about Mr. Musk, but it doesn't take me 1/2 hour to fuel it and go potty, and I don't need a sit-down meal every 2-1/2 hours either.

So even with his superfills, that's still a man-about-town-toy. Nice toy, but still a toy, you have to own a second car or else rent one when going out of town.

mc-
In order to do cell management, the bms has to be built into the battery casing (laptop style) or else you need to bring packs of wires in/out of the casing to the controller. I'm guessing they'd go laptop style, with a controller board sealed inside the battery top. One less set of wires and connectors to worry about that way.

[mcarling]

Originally Posted by hellosailor

In order to do cell management, the bms has to be built into the battery casing (laptop style) or else you need to bring packs of wires in/out of the casing to the controller. I'm guessing they'd go laptop style, with a controller board sealed inside the battery top. One less set of wires and connectors to worry about that way.

The third option is that they might just not do cell management. As far as I can tell, Harley Davidson are not doing cell management with their lithium phosphate motorcycle batteries.

[hellosailor]

Not doing cell management? Isn't that like an agnostic anarchist getting into the debate over Henry-vs-the-Pope? <G>

We know that car batteries routinely get drained to dead flat, with imbalanced cells if you don't take some precaution against that, you're just looking for a battery explosion. Why smart modern cars can't shut down before the battery dies...dunno, but the new alternators often won't charge at all if the battery is <10.5 volts.

[diugo]

Remember there are two flavors of cell management---auto-balancing and disconnect.

Foolish to forego any cell-level disconnect management, but the need for auto-balancing may be unnecessary if the cells are well enough matched to begin with---perhaps even with currents well over C.