Lithium based chemistry for starting batteries

[dreadlocks]

even if its too cold for battery to recharge, its still able to discharge and provide all the buffering needed for the alternator.. so I dont think thats a problem.

Lithium has advantage that load size dont really effect efficiency.. a 20C Starter Load is going to Zap more energy out of a tiny lil AGM than a LFP of same size.. so unless you just gotta crank the crap out of it on a cold morning I doubt its gonna take more than a couple AH out of the battery, and then when it warms back up it'll restore that pretty much instantly.. if you dont get it warmed up thats still enough capacity for quite a few starts, so hopefully one of those runs warms it back up before you drain it.

I could see if you went all LFP house bank and outfitted a nice custom DC charger, adding a Lithium Starter could make things a bit simpler as it could be charged and treated the same.. ie, going months w/out a charge, cutting off charge as soon as it gets full, etc.. but then what are you gonna winch with? a LFP bank capable of handling a winch load would be a rather pricey one... do you want something so bleeding edge to depend on starting it in BFE or something a bit more tried and trued like good old lead.

 

[shade]

There are lots of folks who have the image of a bro-dozer lifted 37" tire, JKU weighing 8,000lbs with a 700lb RTT as the ultimate "overland" vehicle. Lets just say promotion has only a passing connection with reality. Though the dopamine release from buying another widget to bolt on to ones rig is real.

I would love to replace the big lead chunk under my hood as well. So I will be paying attention.

So would I, but I have my doubts about this one. If a company developed a true all-weather/temperature lithium start battery with internal heating, low & high voltage disconnects, and low & high temp disconnects, I think they'd make that a prominent feature in their literature.

 

[shade]

even if its too cold for battery to recharge, its still able to discharge and provide all the buffering needed for the alternator.. so I dont think thats a problem.

Lithium has advantage that load size dont really effect efficiency.. a 20C Starter Load is going to Zap more energy out of a tiny lil AGM than a LFP of same size.. so unless you just gotta crank the crap out of it on a cold morning I doubt its gonna take more than a couple AH out of the battery, and then when it warms back up it'll restore that pretty much instantly.. if you dont get it warmed up thats still enough capacity for quite a few starts, so hopefully one of those runs warms it back up before you drain it.

I could see if you went all LFP house bank and outfitted a nice custom DC charger, adding a Lithium Starter could make things a bit simpler as it could be charged and treated the same.. ie, going months w/out a charge, cutting off charge as soon as it gets full, etc.. but then what are you gonna winch with? do you want something so bleeding edge to depend on starting it in BFE or something a bit more tried and trued like good old lead.

Discharging isn't really a concern, and this battery has a low voltage disconnect. I'm guessing it'll disconnect for an overlimit load, too.

Otoh, I saw nothing in the literature about this battery having internal heating or any kind of charge disconnect. Maybe they have special chemistry that doesn't care if an alternator is keeping the battery at 100% SOC, or trying to charge at too low of a temperature; they don't say.

 

[dreadlocks]

I think they'll make that a prominent feature in their literature.

and the price would reflect that, which it does not.

 

[luthj]

even if its too cold for battery to recharge, its still able to discharge and provide all the buffering needed for the alternator.. so I dont think thats a problem.

Alternators can spike high as well. Think of the change in field current when the glow plugs, or the 100A DC heater (used for cabin comfort) turns off. I have seen alternators running at max output spike over 16V when the load disconnects. This is with a 100AH starter battery as a buffer.

 

[dreadlocks]

If the starter battery is full and not taking a current its gonna do jack squat for a high spike.. lead/lithium or even a big giant cap.. and starter batteries spend a vast majority of their time completely full.. if there's nothing willing to sink that current quickly, its spiking.

Now if the BMS will survive a 16v spike, thats a good question..

 

[shade]

Now if the BMS will survive a 16v spike, now thats a good question..

Nothing about it here.

https://cdn.shopify.com/s/files/1/0249/2618/files/Full_Spectrum_Power_Pulse_IPT_Battery_Details.pdf?16222509600014304953

 

[luthj]

Not necessarily, a lead battery is a capacitor (in addition to a chemical battery), and at high voltages will sink a couple hundred amps for ~50ms, even if its fully charged. There is little else that is pure resistance in a vehicles systems, maybe a few motors etc, everything else is solid state electronics, and a few inductive loads.

 

[shade]

Not necessarily, a lead battery is a capacitor (in addition to a chemical battery), and at high voltages will sink a couple hundred amps for ~50ms, even if its fully charged. There is little else that is pure resistance in a vehicles systems, maybe a few motors etc, everything else is solid state electronics, and a few inductive loads.

Victron appears to be using it that way with their new DC-DC charger.



It's also alluded to in this blog post:
"Alternator rectifier diodes failing because of over voltage after disconnect by a BMS"

Careful - Alternator Charging Lithium - Victron Energy

Charging lithium batteries from an alternator, be that in a boat or vehicle, presents some challenges when compared to the straightforward nature of charging lead based batteries. The video in this blog highlights these lithium challenges and shows you what can happen when things go wrong –...

www.victronenergy.com

 

[john61ct]

Absolutely perfectly fine for cranking anything at all, afa the cells ac

Only a BMS would creat limitations

And the temperature issue, choices are

bring inside to charge
rig a box and preheat
warm weather only

 

[john61ct]

Maybe they have special chemistry that doesn't care if an alternator is keeping the battery at 100% SOC

No such thing

But the market is not aware or does not care about those fine points of optimal longevity, long as it meets warranty specs. . .

 

[shade]

No such thing

But the market is not aware or does not care about those fine points of optimal longevity, long as it meets warranty specs. . .

Five years, but I didn't read the fine print.

Considering the discussions we've had here about environmental concerns and ways to address them, I'm sure it's possible for a manufacturer to address most of them. Hi/lo voltage cutoff, hi/lo temp cutoff, internal heating, cell balancing, external communication & control, and modularity to aid in repairs - all of that could be done well, and tucked into a G31 size case. With the exception of dealing with engine bay heat, an off-the-shelf lithium based battery with those features would seem to tick a lot of boxes. I think that list covers the goals of most DIY designs.

I don't think this battery is the first to put all of that together, though.

 

[john61ct]

The industry relies on consumer ignorance, and since that's 99.99% of buyers, not a problem.

The level of knowledge embedded in threads in forums like this, far surpasses that of 99.3% of customer-facing and non-technical / engineering staff employed by vendors.

And profit margins rule, 98.8% of customers buy on price alone, and if the battery's dead as a doornail in 5 years +1 day, they figure they got a good deal.

There's little incentive to "do it right" as in maximising potential longevity and properly accommodating a wide range of edge-case needs, that just prices them out of the market.

Except for the Victrons / Mastervolt / Lithionics of the world, in it for the long term, pride in the work itself rather than quick profits, building and maintaining a stellar rep over decades.

Few and far between, and soon as bought out by the MBA private equity types watch it go up in a puff of smoke very quickly.

 

[shade]

The industry relies on consumer ignorance, and since that's 99.99% of buyers, not a problem.

The level of knowledge embedded in threads in forums like this, far surpasses that of 99.3% of customer-facing and non-technical / engineering staff employed by vendors.

And profit margins rule, 98.8% of customers buy on price alone, and if the battery's dead as a doornail in 5 years +1 day, they figure they got a good deal.

There's little incentive to "do it right" as in maximising potential longevity and properly accommodating a wide range of edge-case needs, that just prices them out of the market.

Except for the Victrons / Mastervolt / Lithionics of the world, in it for the long term, pride in the work itself rather than quick profits, building and maintaining a stellar rep over decades.

Few and far between, and soon as bought out by the MBA private equity types watch it go up in a puff of smoke very quickly.

John, I never knew you were a cynic.

You're right, of course.

 

[john61ct]

The automated incentive mechanisms of capital create boringly predictable defaults.

Those bravely fighting to rise above that mainstream are to be treasured.