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Lithium Ion Car Battery

11/01/2017 2:34 PM

Something sparked my interest and I was wondering if someone has some real world advice on using a Lithium Ion car battery vs other options.

Porsche offers a Li-ion battery in their cars - an expensive option, but it may be worth the cost.

Benefits:

1. Lower weight

2. Longer life

3. No damage from electrolyte

4. Smaller package

And from a sales/delivery aspect - replacement battery:

1. Less cost to deliver (smaller size and less weight)

2. Less space needed to store batteries

3. Less damage from leaking acid - batteries damaged in the store or on the truck

4. Lower injury claims - moving/carrying heavy batteries

It seems like a no brainer, except for cost. Also, the battery is a Lithium Iron Phosphate.

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#1

Re: Lithium Ion Car Battery

11/01/2017 3:00 PM

But there is that whole catching on fire thing....

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#3
In reply to #1

Re: Lithium Ion Car Battery

11/01/2017 4:25 PM

Very low fire potential with the Lithium-Iron-Phosphate.

Read this write-up from battery university. Unfortunately, the term "Lithium-ion" covers a lot of different batteries. Some are fire hazards, and some like the Lithium Iron Phosphate(LiFePO4) are pretty stable.

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#6
In reply to #3

Re: Lithium Ion Car Battery

11/01/2017 6:31 PM

This is what I heard. Low risk of fire/explosion in Lithium Iron Phosphate battery.

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#2

Re: Lithium Ion Car Battery

11/01/2017 3:35 PM

No thanks.

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#10
In reply to #2

Re: Lithium Ion Car Battery

11/02/2017 9:15 AM

you will have no choice. lithium batteries are going to be the staple. one thing that the original post left out was the perceived health risk with lead batteries. The last lead manufacturing plant in the US was closed down the end of 2013 (more so to restrict the bullet manufacturing in the US, but car batteries use a lot of lead). of course that wont stop the Chinese from importing lead but there is also the whole sulfuric acid thing that people are also concerned with.

what made lithium ion batteries hazardous came from the high energy that is stored in such a compact package. the compact package meant that separators were thinner and since they needed to be porous, there was was the internal shorting from whiskers that grew and pierced thru the separator. another issue was the electrolyte liquid was flammable. lots of work has went into making the separators stronger to inhibit whisker growth and the use of non-flammable electrolyte liquid.

soon this too will go away with the manufacturing of a ceramic electrolyte. the ceramic will stop whisker penetration altogether as well as remove the liquid.

are there still going to be issues, sure but as the research continues, the safety becomes built in. right now the batteries are quite safe, consider the millions upon millions of devices that are out there today that use lithium batteries. not many problems as when there is, the media is all over it.

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#12
In reply to #10

Re: Lithium Ion Car Battery

11/02/2017 11:14 AM

"The last lead manufacturing plant in the US was closed down the end of 2013 (more so to restrict the bullet manufacturing in the US, but car batteries use a lot of lead)."

Perhaps, but with the new administration comes an insane roll-back of environmental, health and safety and business regulations that spell a return of some off-shore industries that had rightly been on the way to the trash heap. Battery manufacture, and bullet casting may well see a resurgence, now.

And if the name Jim Bridenstine doesn't strike fear in you, then you are out of touch or no longer work for NASA.

I don't doubt that advances in technology are coming, but I doubt that I'll ever buy a vehicle with a lithium battery in my lifetime.

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#14
In reply to #12

Re: Lithium Ion Car Battery

11/02/2017 11:32 AM

i guess maybe i am a bit out of touch, maybe i have never really been in touch. I have been here for 30 yrs. i have seen them come and go. i have seen the good days as well as the bad ones.. i am not exactly sure where we stand now... this guy cannot be any worse for the agency than the dismantling that 8 yrs. of the obama administration did.

I am not going to pretend to know what you will or will not purchase but i can assure you that in the next few years, there will be no other choice in a new automobile. As we all know, prices will fall fast with mass production of any new technology (VCR, Microwave oven, home computer, flat screen television, ect., ect.)

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#15
In reply to #14

Re: Lithium Ion Car Battery

11/02/2017 11:53 AM

Well, I dealt with GSFC for years but that ended in 1988. Great group of guys there, and all throughout NASA, I'm sure.

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#19
In reply to #12

Re: Lithium Ion Car Battery

11/02/2017 2:45 PM

One of the things about lead acid batteries that gets overlooked is the high degree of recycling that takes place these days, very little of that makes it into the environment, and the batteries perform well over a wide range of ambient conditions. I do not have the comparison performance data in front of me with respect to the LiFePO4 battery.

Another energy storage battery I have an eye on is something emerging from MIT.

This battery used molten antimony, electrolyte (molten salt of a specific make up), and molten magnesium, with the magnesium floating on top. They have scaled this up to the size of a dinner plate, and are working on one about the diameter of a truck tire. They are sealed units, supposedly with nil off-gassing, and have very many deep cycles capability, high specific power, high energy density, etc.

We will hear more about those in the next decade, but you won't have one in your car ever, most probably. They are for bulk energy storage based on renewable energy.

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#4

Re: Lithium Ion Car Battery

11/01/2017 4:42 PM

Porsche is offering Li-ion batteries as an expensive option. Other manufacturers use Li-ion as standard equipment, to the near total exclusion of other battery tech.

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#5

Re: Lithium Ion Car Battery

11/01/2017 5:04 PM

Road and Track:

"First off, the advantages: Lithium batteries are lighter, can store a charge longer and can withstand charge/discharge cycles better than a lead-acid battery. The ratio of the maximum safe output current possible to the rated capacity of the battery is much higher in a lithium battery; therefore, you need less "rated amps" to accomplish the same amount of work. In other words, they can dump or absorb huge amounts of current in relation to their rating.

Disadvantages: Their output drops much faster than lead-acid batteries as the temperature goes down. If not properly charged, they're much more susceptible to individual cell failures. Unless they're properly constructed with built-in charge circuitry, we really can't consider them plug-and-play compatible with lead-acid batteries. And last, there's the price, as much as $1700 for an OE application, versus maybe $120 for a top-line Sears DieHard.

Now, aside from the damage to your bank account, all the disadvantages can actually be resolved through thoughtful engineering. Unless you own a McLaren MP4-12C, which comes with a lithium starter battery from the factory, the alternator in your car is not designed to properly charge a lithium battery. Some cars, like Porsche's track-oriented models (GT3, GT2, etc.) can be bought with an optional lithium battery. Designed for track use, or even daily use in warmer climates, the battery—which, at just under 13 lb. is more than 22 lb. lighter than the standard lead-acid unit—is built with a charge converter that takes the output from the alternator and converts it for use in the lithium battery. Special circuitry balances the charge current among all four of its internal cells."

http://www.roadandtrack.com/new-cars/videos/a18350/lithium-batteries-not-just-for-hybrids/

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#7
In reply to #5

Re: Lithium Ion Car Battery

11/01/2017 6:57 PM

So the initial price would put me off right away, then you have the other considerations...when all is said and done, this seems money spent without any noticeable advantage in day to day operation...

.."Because of the nominal 3.2 V output, four cells can be placed in series for a nominal voltage of 12.8 V. This comes close to the nominal voltage of six-cell lead-acid batteries. And, along with the good safety characteristics of LFP batteries, this makes LFP a good potential replacement for lead-acid batteries in many applications such as automotive and solar applications, provided the charging systems are adapted not to damage the LFP cells through excessive charging voltages (beyond 3.6 volts DC per cell while under charge), temperature-based voltage compensation, equalisation attempts or continuous trickle charging. The LFP cells must be at least balanced initially before the pack is assembled and a protection system also needs to be implemented to ensure no cell can be discharged below a voltage of 2.5 V or severe damage will occur in most instances."...

So the battery is outrageously expensive by itself, what do all these peripheral systems and components cost....and does anybody know how to work on them?

https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

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#11
In reply to #7

Re: Lithium Ion Car Battery

11/02/2017 9:25 AM

soon the automotive system will be 42 volts. the increase in voltage is to handle all those fancy electronic gizmos that are becoming standard with our automobiles. the weight of 42 volts worth of lead-acid batteries added to the weight of all those high amp wiring harnesses mean less efficiency on the bottom line.

the automotive industry WILL go with lithium batteries, and after that will be silicon.

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#16
In reply to #11

Re: Lithium Ion Car Battery

11/02/2017 12:51 PM

Well I'm all for raising the voltage, don't know why it's so low to begin with....48 volts seems a better choice though...

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#17
In reply to #16

Re: Lithium Ion Car Battery

11/02/2017 1:22 PM

it could be 48 i may be remembering incorrectly... 40 something volts..

i was sitting in on a lecture and the speaker from one of the auto industry leaders put up a chart mentioning the fact. they also said methane was on the radar, and oil has hit its peak and will be trending down into the future which is probably why the Saudi's have dropped the price of oil to ridiculously low prices.. (well that and the fact that the US can compete with the higher price oil) they know once the thirst is gone, so is their wealth. i read somewhere that the US is now producing enough gasoline that it is exporting it despite there hasn't been a new refinery built since the 70's.

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#20
In reply to #11

Re: Lithium Ion Car Battery

11/02/2017 3:22 PM

"...weight of 42 volts worth of lead-acid batteries...."

The weight of a lead acid isn't necessarily greater for a perspective 42 volt battery in a 42 volt system doing the similar work as a 12 volt battery in a 12 volt system.

"... added to the weight of all those high amp wiring harnesses mean less efficiency on the bottom line..."

Higher voltage wire harnesses would be lower amperage to drive similar processes. Beyond that, even in Backwardo World, changes to the harness aren't something specific to lead acid batteries.

AFAIK, the automakers were into that whole 42/14 volt autobattety system about 2 decades ago....haven't heard much since about it.

Lead acid, even with its weight easily wins the majority of the non-hybrid automotive battery market....far and away. Until non-hybrids are no longer the dominant type of vehicle, lead acid will be the dominant type of battery installed.

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#21
In reply to #20

Re: Lithium Ion Car Battery

11/02/2017 4:37 PM

I heard about the 42V battery years and years ago - maybe a couple decades? Back then they said it would be a couple years away.

In the auto industry, standards like 12VDC systems are going to be hard to get rid of. There's too many cars running 12VDC and having to retrain mechanics will be costly. Also, there's going to be some mistakes made - mechanic puts a 12V part into a 42V system, etc. There's also a safety issue - it's hard to get shocked by a 12VDC battery, but 42VDC is a different story.

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#28
In reply to #21

Re: Lithium Ion Car Battery

11/03/2017 9:14 PM

Limiting the risk and severity of people getting shocked was one of the factors (likely the big factor) that kept the voltage from being much higher.

Costs for motors and wiring can be much lower at higher voltage, overall efficiencies can be higher as well.

Generally organizations have rated voltages have considered voltages under around 50V dc as 'safe'. IEC calls less than 60 VDC 'safe'. Osha makes a significant distinction at above/below the 50 VDC level.

.

I'm not saying you can't get shocked with 48V dc....but people also get shocked with 12V or less.

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#30
In reply to #28

Re: Lithium Ion Car Battery

11/04/2017 1:03 AM

GA to you! Good info on why voltages are lower and OSHA thresholds - legal and compliance people look for this.

When I was doing my undergrad, I remember the cost savings with higher voltage DC. I also remember the danger of higher voltage DC too.

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#29
In reply to #21

Re: Lithium Ion Car Battery

11/03/2017 11:18 PM

Many hybrid and fully electric vehicles are running electrics, both DC and AC, in excess of 300 volts, and voltages over 1000v are beginning to appear.

Many normally powered vehicles have HID headlights fitted which require in excess of 20,000v to start, and around 90v to maintain operation.

These voltages pose very real risks to persons involved in maintenance or accident recovery events.

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#8
In reply to #5

Re: Lithium Ion Car Battery

11/01/2017 9:05 PM

So, figure one $1700.00 battery is equivalent to 25.5 years worth of $200.00 batteries that last 36 months each?

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#22
In reply to #8

Re: Lithium Ion Car Battery

11/02/2017 4:43 PM

From an economic standpoint, you are correct. From a performance standpoint, I think we'll see more manufacturers using them. The lower weight and smaller packaging are important for performance cars.

Remember about a decade ago, when GM stopped putting spare tires in their cars. They claimed it was to increase gas mileage, but it's pretty obvious that it's a cost saving measure. No jack, spare tire, wheel, lug wrench, etc. Just a can of fix a flat, or on the more upscale models, a cheap tire inflater. The luxury cars went with run flats, which are very expensive and they ride harder. I've taken the run flats off my cars and put regular tires on them. The only problem is that I don't have a spare, so I need roadside assistance coverage.

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#9

Re: Lithium Ion Car Battery

11/01/2017 9:28 PM

Lithium Iron Phosphate batteries - often called LFP or LiFePo4 are just one form of Lithium battery technology.

They have a longer cycle life, but a somewhat lower energy density than the Lithium Cobalt - LiCoO2 technology that SE alludes to in his post, LiCoO2 is the one most often responsible for the many fires involving these cells.

LFP cells are virtually impossible to make burn - if punctured they will certainly produce copious amounts of smoke, but no flame as is the case with the Cobalt forms.

As stated, they do have many advantages over Lead Acid(LA) technology, mainly being weight, size and cycle life, with the greatest advantage being their very low internal resistance which gives them the ability to charge rapidly and also torelease large amounts of energy whilst maintaining their terminal voltage.

It is this advantage that has made them a preferred option for battery jump start packs etc, a small - say 18Ah LFP battery can be used to jump start a large vehicle motor where a very much larger and heavier LA battery would be required to achieve the same result.

A further advantage is that they do not need to be maintained in a fully charged condition, LA cells must be returned to full charge as soon as possible after discharge to prevent sulphation and consequent early demise and should never be stored in a partially charged condition, LFP on the other hand can be left in a partially charged state for long periods, and latest information suggests that they actually live longer if stored at less than full charge condition.

Another advantage is that, due to the very low internal resistance, they charge very quickly with no absorption or float stage - there is no Peukerts effect which is what limits LA batteries in their ability to both charge rapidly, and provide high discharge currents whilst maintaining their terminal voltage.

A 12v LFP battery's terminal voltage will remain above 13v until the battery is almost flat and then drops off very rapidly. While this is a great advantage, it also becomes a liability - most load controllers measure voltage to determine when to shut down to protect the battery, with 11.5v being a common point chosen for this, but LFP can pass through this point in milliseconds when under heavy load thus resulting in destruction of one or more cells - they rarely recover from total discharge.

This brings us to LFP's disadvantages, LA batteries have a self balancing feature - a 12v LA battery consists of 6 cells each of about 2.15v when fully charged. They are normally charged at voltages between 14 and 14.8v (depending on their particular chemistry), at about 14.4v (2.4v per cell) the electrolyte begins to boil and release heat and gas, the voltage then rises much more slowly. Approaching full charge, one or more cells may be at the 2.4v stage whereas others may be lower. Consider if we have 1 cell at 2.4v and 5 at 2.3v - this gives us a terminal voltage of 13.9v - too low to trigger the charge controller to go to float. The release of heat from the higher cells allows any slower cells to catch up until the cut off voltage for the charge controller has been reached. They also lose their terminal voltage more evenly, which allows a load controller to operate effectively.

LFP batteries have no self balancing ability, a new generation 12v LFP battery consists of 4 cells each at about 3.45v when fully charged (13.8v for the battery). A cell will begin to boil if its voltage exceeds 4.5v. Typical charge setting would be at 14v to 14.2v ie. 3.5 to 3.55v per cell. if a cell reaches its critical voltage of 4.5 v and remains on charge, its voltage will rise rapidly and the cell will expand and possibly rupture - these cells are not known to erupt in flame.

Consider a charge controller set at 14.2v cut out, due to cell imbalance, 1 cell reaches 4.5v while the other 3 are at 3v, a total of 13.5v - the charger remains on and the high cell is destroyed - this is why individual over voltage protection of cells is essential. As stated earlier, under voltage is also a killer, so under voltage protection is also necessary.

This protection or BMS system can form a fair percentage of the cost of manufactured Lithium batteries, but on a cycle life vs cost per Ah basis LFP is ahead of LA.

LFP is fast becoming the preferred option for recreational vehicle use, I personally have a 600Ah LFP battery in my RV, consisting of a set of 8 x 300Ah prismatic cells in a parallel/series configuration. They are charged via standard LA type solar and mains chargers and protected by my own designed and built over and under voltage systems.

This setup gives me an available 480Ah with 20% reserve (they can be discharged as low as 5% SOC, but that can be difficult to control so I stick to 20% for safety) and a 4000 cycle life at normal 50% depth of discharge (DOD), with a total weight of just 78kg and volume of 0.045m³.

For an equivalent usable capacity of LA chemistry (50% DOD) I would require 960Ah or 5 x 190Ah 12v batteries weighing in at around 280kg with a volume of around 0.15m³ and a cycle life of just 200-300, so that's over 3.5 times more weight, 3.3 times more volume, and 13 times less cycle life, and the LFPs can be safely housed inside the RV as there are no dangerous gassing or ignition concerns.

Then there's the usability of that power - because of the low internal resistance and consequent ability to maintain terminal voltage at high discharge currents, I can run - via an inverter - my air conditioner or my microwave or my electric kettle and toaster or my induction cooker or even the electric element in my hot water service if desired. If I tried to run the element of the heater or the microwave or even tried to start my air conditioner on the LA setup the resultant voltage sag would cause the inverter to switch off within seconds. Faster charge times also mean that the rooftop solar can replenish the SOC much faster than would otherwise be possible - so less solar can be deployed if desired. My setup is now approaching 5 years old - the expected life of most LA chemistries - but is in as new state with capacity still over 95%.

Sure, initial setup costs more for the LFP - roughly twice as much (you can make your own pack for a fraction of the cost of store bought batteries), but cost per life cycle is $7.50 for the LA vs just $1.20 for the LFP and the availability of so much power makes it a very successful choice, and considering that I would now be looking at replacing an LA set after 5 years, the initial extra cost becomes just a prepayment and then a 33% saving another 5 years on. Some folks keep their LA batteries longer than 5 years, but their capacity at that time is always considerably less than the plated capacity, and their performance is markedly lower due to sulphation and grid corrosion.

Photo of my 600Ah setup with cell protectors on top.

Battery currently at 39% state of charge, a good SOC while in storage, can't do that with LA.

Current battery voltage at 39% SOC. A LA battery would be at about 11.9v at this SOC and dying fast in storage.

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#13
In reply to #9

Re: Lithium Ion Car Battery

11/02/2017 11:14 AM

Geez! You have me turning green with envy! I have been looking at putting a LiFePo4 setup on my camping rig for the last 2 years. The worst part is trying to convince my wife that it is worth the initial expense.

I already built 5 x 120W solar panels for a total of 600W (provided everything is perfect). I can add another 300W to that before I have to "up" my charge controller. The (eventual) 900W will run a small air conditioner + the refrigerator (run on propane after dark) + lights...

"LFP is fast becoming the preferred option for recreational vehicle use, I personally have a 600Ah LFP battery in my RV, consisting of a set of 8 x 300Ah prismatic cells in a parallel/series configuration. They are charged via standard LA type solar and mains chargers and protected by my own designed and built over and under voltage systems."

^Would you be willing to share?Please, Please, Please! That would save me having to reinvent the wheel!

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#24
In reply to #13

Re: Lithium Ion Car Battery

11/03/2017 8:31 AM

I have been getting emails from a company in China that makes Li-PO battery packs and sells them with or without PV panels.

One thing I noticed about run-of-the-mill inverters is that you have to watch the inrush current when starting things like small AC motors, since this will absolutely cause a trip.

AC units are very power intensive as you know, so how does it play with your inverter every time it cycles the compressor?

I guess we will have to wait for the update (a new thread perhaps?).

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#25
In reply to #24

Re: Lithium Ion Car Battery

11/03/2017 10:48 AM

Just watch the specs on some of that stuff.

I've got a 2KW pure sine wave inverter (continuous, 4KW peak) that should handle the load. I also have some huge honking caps from an old VFD that should help.

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#26
In reply to #25

Re: Lithium Ion Car Battery

11/03/2017 10:53 AM

The cheap ones at the auto parts store are anything but pure sine wave, and they can never handle high current devices. I have a 1/2 HP electric motor driving a mini-lathe, and my 800 W inverter simply cannot handle starting that motor.

You, however, know a lot better what works where. I salute your efforts. I expect a full report by Monday week.

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#27
In reply to #24

Re: Lithium Ion Car Battery

11/03/2017 5:54 PM

Many people use inverters that are far too small for the intended load, failing to take into account the starting currents involved. It's often not the inverter that can't handle the load, it's the inability of the battery to maintain output voltage under high load that causes the problems

I use a 2800w continuous, 5600w peak PSW inverter - you can see it behind the battery in the photo - the AC unit is a standard Ibis rooftop one as commonly seen on RVs, and draws about 6 amps when running and around 35 when starting, that's about 700 amps instantaneous from the battery on start.

I originally had a 675Ah Lead acid setup consisting of 3 parallel pairs of 225Ah 6v batteries that weighed in at 185kg and filled the entire box that you see in the photo. Each battery had a listed internal resistance of 1.5 miiliohms so that's 3 milliohms for the series pair - a voltage drop of 2.1v at 700 amps = battery output of just 10.7v.

Further exacerbating this was the fact that the batteries just could not supply the required 700 amps, and so the compressor would labour longer on trying to get up to speed, and the inverter would shut down to save itself.

Even with the pack fully charged, and short 50mm² cables feeding the inverter, the battery voltage would drop close to 10.5v which is considered dead flat for a 12v LA battery.

With the LFP setup I can actually run the AC and the Microwave at the same time (although I prefer not to stress the inverter that much) and the battery voltage never drops below 12.5v even on hot start for the compressor.

It is the ability of LFPs to supply huge currents for long periods with minimal sag that allows the use of high drain appliances.

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#23
In reply to #9

Re: Lithium Ion Car Battery

11/02/2017 4:50 PM

Great info! And you're using the LFP in your own RV, so you have real world experience.

Thanks for sharing.

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#18

Re: Lithium Ion Car Battery

11/02/2017 2:37 PM

This is a safer battery than some of the Li+ varieties.

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