lithium iron phosphate trolling motor batteries ?

[CP]

Are they worth the money?  Prices keep coming down and the weight reduction is pretty compelling.  Any downsides beside cost?

[Hilltop123]

 Along for the ride.........

[scotsman]

You’ll need a different charger. Lithium batteries can be quickly ruined by using a charger designed for lead acid Types.

[CP]

According to Battleborn, a standard charger set to the AGM setting is “great”.

https://battlebornbatteries.com/charging-battleborn-lifepo4-batteries/

They recommend a bulk and absorption voltage of 14.4 V. Float is not necessary but as long as the float is less than 13.6 V it “is fine”

I would expect the battery’s BMS to cut off charging when the battery is fully charged, so I don’t see why float would be an issue.

But my old “dumb” chargers don’t go over 13.3VDC so they aren’t going to cut it.

I have a wall mounted Charles that charges at 14.2 and floats at 13.4 when on AGM setting.  Should work fine as long as I bring the battery to the charger.

[Stein]

I would be pretty careful with any lithium battery.  Battle Born doesn't make the batteries they sell, so I would look other places for confirmation on safe charging. In the article linked, they mention "A float is unnecessary, since li-ion batteries do not leak charge" which is incorrect as they have self discharge just like any battery and the fact they used a term like "leak charge" leads me to believe they aren't overly educated on the topic.

Lithium batteries have a very nasty tendency toward thermal runaway.  The lithium iron phosphate batteries are supposed to be safer as they are more stable, but they are still pretty new and I haven't seen a bunch of data on them yet.

No way I would leave any lithium battery larger than a laptop charging unattended, much less on an AGM charger.  It might end up being OK, but I would wait for the AGM chargers to be certified to charge them before I got too excited about using one.  Just because they may have solved one problem doesn't mean they didn't create another one (or even not solve the first one).

Even with lithium iron phosphate, a bunch are likely coming out of China and they can vary in quality dramatically.  I would only trust known manufacturers that either produce their own cells or are pretty transparent about where they get them.  I wouldn't be surprised if you saw mislabeled cells on the market just like anything else coming from China.

[CP]

Well, that’s a buzz kill.  I was under the impression LiFePO4 is safer than Li-ion or lead acid.  They don’t even require venting.  I’ll do some more research.

[Stein]

They probably are, at least in the aspect of thermal runaway.  I don't know that has been fully tested yet and even if it was, would be based on a certain charger or charge profile.  I'm not saying they aren't the greatest thing since sliced bread, I'm just saying I'm not leaving them plugged in in my garage or next to my house until we know more.

The guys like the one you linked "assemble" the batteries which means they buy them from someone, package them in a nice looking container and sell them under their brand.  The are likely not intimately familiar with the chemistry or manufacturing process of the battery or the chargers they sell - not a dig as nobody in their place does.  Same with Cabelas, they slap their label on a reel and have no idea how it was designed or built.  Nearly every battery manufacturer will tell you how safe their batteries are and how awesome and unique their manufacturing process is, kind of like every industry.

There are big challenges with lithium ion batteries in manufacturing, a tiny issue at the factory leads to big problems in the field.  At one factory, they had a tiny problem with one of their suppliers and it ended up in fires in the field.  One of the challenges with new technology in batteries is we only know what went wrong with the last ones, i.e., we don't know what we don't know.  It might be an overly cautious perspective, but I'm pretty close to some of the issues in the past and am likely over sensitive.

[CP]

Gotta love YouTube.  This guy tears apart $1000 batteries to see how they are constructed.  Most seem to be junk, but some are very well made.

I’m leaning toward the SOK.  Looks well-made and thoughtfully engineered.  I like the idea of serviceable battery, not so sure of the steel case though. 

[CP]

I ordered a SOK 100ah.  $570, free shipping, no tax when ordered directly.  Compare that to $993.40 for a Battle Born.

https://www.sokbattery.com/100ah-12v-lifepo4-deep-cycle-battery.html

Great customer service; they answered my questions almost instantly.  Charging isn’t a problem, any charger that provides about 14.6V will work.  The BMS protects for over & under voltage, high & low temperature and over current.

Shipping is slow but I don’t need it right away.  Not really fishing weather out there.

If it works out, I’ll buy some more for my off-grid cabin.

[bassquatch]

I have been running my Ionics since July-ish and will never go back! 

[CP]

I have been running my Ionics since July-ish and will never go back! 

Nice.  That's a lot of battery.

[Stein]

It's tempting, I could pull 80 pounds out of the back of my boat but it would cost at least $1100 to do it.

[Stein]

I ordered a SOK 100ah.  $570, free shipping, no tax when ordered directly.  Compare that to $993.40 for a Battle Born.

https://www.sokbattery.com/100ah-12v-lifepo4-deep-cycle-battery.html

Great customer service; they answered my questions almost instantly.  Charging isn’t a problem, any charger that provides about 14.6V will work.  The BMS protects for over & under voltage, high & low temperature and over current.

Shipping is slow but I don’t need it right away.  Not really fishing weather out there.

If it works out, I’ll buy some more for my off-grid cabin.

Did you happen to ask them about the discharge current?  It lists 100A but I haven't been able to find any data on whether you can run that continuous or only for 3 seconds?

There are good uses for these, but they don't seem to be great starter batteries unless you go pretty big.  I'm thinking I only need maybe 50-60 Ahr but the discharge current may not support my monster pot puller.

[CP]

I ordered a SOK 100ah.  $570, free shipping, no tax when ordered directly.  Compare that to $993.40 for a Battle Born.

https://www.sokbattery.com/100ah-12v-lifepo4-deep-cycle-battery.html

Great customer service; they answered my questions almost instantly.  Charging isn’t a problem, any charger that provides about 14.6V will work.  The BMS protects for over & under voltage, high & low temperature and over current.

Shipping is slow but I don’t need it right away.  Not really fishing weather out there.

If it works out, I’ll buy some more for my off-grid cabin.

Did you happen to ask them about the discharge current?  It lists 100A but I haven't been able to find any data on whether you can run that continuous or only for 3 seconds?

There are good uses for these, but they don't seem to be great starter batteries unless you go pretty big.  I'm thinking I only need maybe 50-60 Ahr but the discharge current may not support my monster pot puller.

I didn't ask about max discharge.  But it does list 100Amps on the battery box. 

Shoot them an email, they are very helpful:

https://www.sokbattery.com/contact

[CP]

Found it:

100A continuous, it's in the spec sheet:

https://www.sokbattery.com/pub/media/sparsh/product_attachment/SK12V100-0915.pdf