Lithium Batteries: What You Need To Know

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And yet for most of us, LiFePO4 is not ready for prime time on our bikes. The rated amp-hours are based on lead equivalent (Pb-Eq) and real usable amps are about 25 to 33% of the rating on batteries like Shorai. So that LFX18A1-BS12 Shorai has about 6 amps to give tops. Lots more here https://advrider.com/forums/showthread.php?t=757934

I'm not saying LiFePO4 can't be used, especially where the battery is not subject to very cold temperatures, but be prepared to spend a lot of money and buy oversized.

 
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Hmmm. Quote from the referred article:

The LiFePO batteries will charge a lot faster than an AGM or lead acid battery. With a 10-15 AMP charger designed for the LiFePO batteries you can get a full charge in as little as 15 minutes!
Now, I don't know what capacity battery the writer was referring to, but 15 amps, 15 minutes = 3.75 ampere-hours. Assuming physics hasn't changed considerably in the last few days, that could not charge a typical 12 ampere-hour motorcycle battery unless it was already nearly charged, in which case what are they bragging about?

Having said that, the charger linked to says it's an Antigravity 8-amp charger (not 10-15). Maybe they're focussing recovered gravity waves into the battery in parallel with the current to charge the battery more quickly.

 
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Here's the info from the Alien Motion website: https://www.alienmotion.com/faq.html

"Just as you can not use any charger with any lead acid battery, you also need to be aware of what you are putting into your Alien Motion battery as well. To achieve a full charge, our AM4 battery will need to be charged at 14.4V DC at a maximum of 10 amps, the AM8 and AM12 will be happy with the same voltage, but can utilize as much as 20 amps for a quicker charge time. The advantage to you is extremely fast charge times compared to lead acid. Our products will fully recharge in as little as 15 minutes as opposed to the hours that lead acid requires. When you combine this with extremely low self discharge rates, charging should not be a frequent proposition for Alien Motion batteries."

I don't claim to be an electrical engineer, but with the balance charger maybe it can charge that fast because it is charging the cells individually. That would make sense to me. If you are simultaneously charging multiple smaller cells at a fast rate as opposed to charging one large cell.

 
Here's the info from the Alien Motion website: https://www.alienmotion.com/faq.html
"Just as you can not use any charger with any lead acid battery, you also need to be aware of what you are putting into your Alien Motion battery as well. To achieve a full charge, our AM4 battery will need to be charged at 14.4V DC at a maximum of 10 amps, the AM8 and AM12 will be happy with the same voltage, but can utilize as much as 20 amps for a quicker charge time. The advantage to you is extremely fast charge times compared to lead acid. Our products will fully recharge in as little as 15 minutes as opposed to the hours that lead acid requires. When you combine this with extremely low self discharge rates, charging should not be a frequent proposition for Alien Motion batteries."

I don't claim to be an electrical engineer, but with the balance charger maybe it can charge that fast because it is charging the cells individually. That would make sense to me. If you are simultaneously charging multiple smaller cells at a fast rate as opposed to charging one large cell.
You have to charge all cells in series, there are only two terminals. Even at 20 amps, 15 minutes, that's 5 ampere-hours of charge. I strongly suspect the electrolyte is concentrated acidic snake-oil.

I retired from electronic engineering 7 years ago, so maybe fundamental physics has changed since I was working.

Sorry, I claim a totally misleading BS advertisement.

 
You have to charge all cells in series, there are only two terminals. Even at 20 amps, 15 minutes, that's 5 ampere-hours of charge. I strongly suspect the electrolyte is concentrated acidic snake-oil.

I retired from electronic engineering 7 years ago, so maybe fundamental physics has changed since I was working.

Sorry, I claim a totally misleading BS advertisement.
You may be right. I would add that the balance charger has 5 wires going into the battery though. I don't know what the pin out is exactly, but I suspect a ground and one positive wire per pair of cells in an 8 cell battery.

The balance chargers typically are brand specific and they have a special little port you plug into. I also suspect they are mostly brand specific because of the charge port shape and pinout. The chargers would likely work on different brand batteries if you made the pinout and plugs match.

 
The nominal voltage for a lithium iron phosphate cell is ~3.2 volts. A battery only "needs" 4 cells for 12.8V although there may be a series-parallel arrangement using 8 cells (or other multiple of 4).

 
Wow, such strong opinions.

I have a Shorai 18 whatever. I have had it for a little over two years. It has never let me down and has cranked alot longer than I would have thought a bike battery could when I had a bout of FSS. It has only been on a charger once and it was a regular one sitting in my garage. I have nover had to do anything special to it or for it. It weighs in at next to nothing, and works really well. The only two times it let the odo and clock reset were when I left the ignition on for a few hours and the FSS incident. It is one of the most cost effective ways to lighten a bike in terms of $/lb. My buddy with his Ducati Monster is planning to get one when is battery quits. Granted, 9 pounds mean more on a Duc than on ours but lighter is always better in my opinion. I just can't afford carbon fiber wheels yet.

When I replace it it will be another but it will be one physically bigger as the 18 is quite small.

 
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You have to charge all cells in series, there are only two terminals. Even at 20 amps, 15 minutes, that's 5 ampere-hours of charge. I strongly suspect the electrolyte is concentrated acidic snake-oil.

I retired from electronic engineering 7 years ago, so maybe fundamental physics has changed since I was working.

Sorry, I claim a totally misleading BS advertisement.
You may be right. I would add that the balance charger has 5 wires going into the battery though. I don't know what the pin out is exactly, but I suspect a ground and one positive wire per pair of cells in an 8 cell battery.

The balance chargers typically are brand specific and they have a special little port you plug into. I also suspect they are mostly brand specific because of the charge port shape and pinout. The chargers would likely work on different brand batteries if you made the pinout and plugs match.
With 5 leads, they may well balance the charge in each cell, which in principle is a good idea. But that suggests they fear the cells have different characteristics, and the more fully charged cells would be damaged by extra charging time. Which begs the question of charging on a bike, where there is no provision for charge balancing, and charging current of the order of 20 amps is readily available and likely on a battery that isn't fully charged.

And, however they individually select cells to charge, even 20 amps into a fully discharged 12 ampere-hour battery will at best take 12/20 hours or 36 minutes. Even if only one cell is fully discharged. You can't create charge out of thin air.

What might be theoretically possible is that they take the 14 volts at 20 amps, convert it to a quarter of the voltage and 4 times the current (3.5 volts, 80 amps) to charge one of the 4 cells. That would be difficult to do cheaply, and 80 amps charging rate might degrade the already bad cell further.

I've nothing against Lithium-whatever batteries in principle, I just don't like advertisements that are, at best, misleading.

 
Dunno 'bout all the long talk, but I had a Shorai fer a couple years, ('Til I wadded that FJR.) and it started the bike just fine in temperatures down into the upper "20s". Mah heated gear worked too. When the battery in my current FJR dies, I plan on get'in me another one. That's all I know 'bout lithium. Well, that and them lithium crystals they had on Star Trek.

 
I'm sure I'll jynx myself by stating this, but I have the same battery on my bike that it had when I bought it used in '09. Never been on a charger, sits in an unheated garage for almost 6 months a year. Has started every time. I have no idea what brand/model it is. The only thing I run besides the bike itself is power to a GPS.

Of course, when the arctic thaw finally comes later this spring, now that I've put this out there, it will probably be deader'n a door nail...
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There are a number of styles of lithium/iron batteries that perform quite differently because every LiFe battery manufacturer has their own special roll for output electrodes and cell connections. At one end, the round cell LiFe batteries are a glorified tool battery pack adapting existing cells to a motorsport battery pack and at the other end is Shori, a maturing product with purpose designed innards. Neither LiFe or PbSO4 batteries are perfect though the Shori is much closer to PbSO4 batteries with fewer drawbacks than the LiFe competitors and fewer liabilities than the PbSO4 batteries. Earlier Shori batteries did have some issues, that comes with being a bleeding edge innovator. As time has gone on Shori has done a good job of continually fixing issues and getting better.

For dollar to performance the very mature lead acid battery is hard to beat. For a lotah dollah more, the lithium/iron batteries lose ~90% of the weight and offer a bit more cranking voltage at normal 3 season temperatures.

Please don't try this it is demeaning and degrading, but if someone were to look at Past Posts on the Forum, there is a lot of information and experiences that could be found under lithium and LiFePO4 as guide words.

 
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I had an early Shorai. It failed after about a year and was replaced under warranty. I still have the replacement, though I no longer have the NT700 in which it was mounted. I use it for various cases when I need a 12V source for something or other. The replacement is a few years old.

I put an EarthX in my FJR. (The Shorai is the wrong size for the FJR). It's coming out of its 2nd winter. Nothing particular to report. A bit weak when I have to start the bike after sitting in below-30 deg weather for awhile, but it starts the bike fine and nothing else to note. These have internal circuitry to manage the cell-balancing, so no special charger required. One battery tender they recommend is the Battery Tender Junior. I happened to have one of these, but it doesn't get used, as I've found no need to baby this battery.

 
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Dunno 'bout all the long talk, but I had a Shorai fer a couple years, ('Til I wadded that FJR.) and it started the bike just fine in temperatures down into the upper "20s". Mah heated gear worked too. When the battery in my current FJR dies, I plan on get'in me another one. That's all I know 'bout lithium. Well, that and them lithium crystals they had on Star Trek.
DI-lithium crystals!

 
Had a Shorai sized 18 in my Ducati. Oversized.

Although self discharge was well less than lead-acid, it still required charging during the winter.

The battery failed to crank the engine fast enough to start on any cold yet ridable morning, say 50F.

After two years it failed.

The end.

 
Decided to take the Shorai journey a couple of months ago. It's not been in very long but no issues with starts down into the mid 40's.

 
Decided to take the Shorai journey a couple of months ago. It's not been in very long but no issues with starts down into the mid 40's.
As mentioned in an earlier post, Shorai has been making steady improvements. The Shorai someone bought 3 years ago is not the same Shorai that you would buy today. Living in Aridzonia below 5k feet altitude you should never have a starting problem with the Shorai, you will be finding out how the Shorai survives life in an oven.

 
I'm trying to understand the whole Lithium battery "upgrade"

I've had a lot of bikes and all have had regular lead acid and all worked fine, providing the charging system was OK.

As for saving a few pounds...on a bike the size of an FJR..?!?!?

 
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