LTO bank vs LiFeP04 for daily system

[hispls 5,000+ posts]

I'm in central Florida, so cold isn't really a thing. 120+ In-car Temps are a thing tho.

I still can't figure out LTO vs LiFeP04. I know the voltage difference, but I've seen LTO punctured and not catch on fire so that sounds better to me. I cannot run my voltage above 14.8 or my car will throw a tantrum so going with a 6s pack is a no-go. I will have to double check my cold start voltage, but I beleive it is 14.3. Whatever I buy will get used until I switch cars or upgrade my system again(hopefully never). I guess this has turned into batteries or alternator for the moment. Is a 320a alternator from mechman(assuming it will fit) better than 40ah of LTO or 48 ah of LiFeP04 for daily use? I might be able to stretch it to 80ah of LTO if you have em or 60ah of LiFeP04 from the pre-built guy.

Matt

The LTO cells are -40 to 60C temp range so fine for anything in the cabin, I'd probably not want to mount them in the engine bay though.

LTO is just a slightly different flavor of LiFePO and AFAIK the LiFePO are pretty stable as far as not being prone to catastrophic failure (read: FIRE). LiPo are the ones that really go up like a white phosphorous grenade if things go wrong, they're a different animal though.

I run 6S banks in my Jeep and my brother's Civic with good results but at our charging voltage we are leaving a bit on the table and I think either could drop down to 5S banks and perform as well or better.

Back when I competed in 2000W class I used a HO alternator and one additional AGM in the back and still had some pretty big voltage drop when I went hard on things, but I was running one of the under-rated Korean 2K boards and at .5 ohm.

Alternator is a great option if it's easy to swap in your vehicle as it actually makes current and it takes up zero space in the vehicle. That said I don't believe a HO alternator will outlast any lithium bank and you may or may not be able to port it to a different vehicle when and if you have to get another car. Might want to get a few alternator quotes and weigh your decision with that in mind. Nate up at Excessive Amperage has always done me right and he's either in or just over the border from Florida.

 

[mat3833 10+ year member]

The LTO cells are -40 to 60C temp range so fine for anything in the cabin, I'd probably not want to mount them in the engine bay though.

LTO is just a slightly different flavor of LiFePO and AFAIK the LiFePO are pretty stable as far as not being prone to catastrophic failure (read: FIRE). LiPo are the ones that really go up like a white phosphorous grenade if things go wrong, they're a different animal though.

I run 6S banks in my Jeep and my brother's Civic with good results but at our charging voltage we are leaving a bit on the table and I think either could drop down to 5S banks and perform as well or better.

Back when I competed in 2000W class I used a HO alternator and one additional AGM in the back and still had some pretty big voltage drop when I went hard on things, but I was running one of the under-rated Korean 2K boards and at .5 ohm.

Alternator is a great option if it's easy to swap in your vehicle as it actually makes current and it takes up zero space in the vehicle. That said I don't believe a HO alternator will outlast any lithium bank and you may or may not be able to port it to a different vehicle when and if you have to get another car. Might want to get a few alternator quotes and weigh your decision with that in mind. Nate up at Excessive Amperage has always done me right and he's either in or just over the border from Florida.

It's going to be around 180 bux for the alt depending on what's available. I went back to him because he built a 280a(i beleive) alt for my Malibu that got donated to a buddy after I got the jetta. That alternator has been kicking out power for going on 10 years now, drowned in a lake once, survived a small engine-bay fire, and delt with whatever systems my buddy has had. If I can get an upgraded alt then I can run a slightly smaller LiFeP04 bank. LTO is looking like less of a possibility since I would need to drop my charging voltage potentially.

I guess it boils down to 40ah of yinlong+alt or 30AH of headway(prebuilt) with an alt. The headway includes the balancer and cell monitor and has a voltage/current display I can remote mount.

Does anyone sell comparable LTO prebuilts? I know LTO is a better battery overall from a power and longevity perspective if it's used in its means, but it's hard to look away from a pre-built I can just bolt some ring terminals on and be done.

Matt

 

[HondaCRV03]

I know you'd rather go pre built but I'd like to say I was able to build my 32ah headway bank in about 20 minutes.



This helped me. It can probably do the same for you

 

[mat3833 10+ year member]

I know you'd rather go pre built but I'd like to say I was able to build my 32ah headway bank in about 20 minutes.



This helped me. It can probably do the same for you

I know it's that easy to make a bank. But I still need to make a case, add a balance board, wire in a voltage display, etc. I wouldn't save much money building a headway bank versus using the guy linked on the first page. After getting a case and everything included I'm not saving more than a few dollars unless I can get a deal on cells.

I would be able to build a Yinlong 40ah bank for about 400 plus the cost of a voltage meter, haven't found a standard case yet.

Matt

 

[winkychevelle 10+ year member]

I know it's that easy to make a bank. But I still need to make a case, add a balance board, wire in a voltage display, etc. I wouldn't save much money building a headway bank versus using the guy linked on the first page. After getting a case and everything included I'm not saving more than a few dollars unless I can get a deal on cells.

I would be able to build a Yinlong 40ah bank for about 400 plus the cost of a voltage meter, haven't found a standard case yet.

Matt

I don't think there really is a standard case since you can lay the cells out in so many different variations. If you do decide to diy Coventry industries likely has the bars you would need.

Nothing is wrong with lto other than min voltage to charge. At 5s instead of 6s max charge would be 14v which is why xs and d4s chose that configuration. Down side is alot of modern cars can spike higher than that.

You could add a voltage regulator to your current alt but you stated it was going to bug you cars computers. That leaves lifepo4 as the best option.

This is another alternative to headways and are arguably better cells. They just aren't as popular and finding bars may be more difficult.

4PACK LISHEN 8.5AH 30C 3.2V LifePo4 Prismatic Lithium Cells

4PACK LISHEN 8.5AH Battery has grown its annual production capacity up to 10GWh and has maintained the major market. Lishen prismatic lithium cell.

srikobatteries.com

 

[HondaCRV03]

Ah ok. Got it. Yeah all I did was add the balancer to mine. I believe @KicktheSDbasshead was willing to sell some. I could be wrong. If I am, please correct me

 

[KicktheSDbasshead]

Ah ok. Got it. Yeah all I did was add the balancer to mine. I believe @KicktheSDbasshead was willing to sell some. I could be wrong. If I am, please correct me

Yep headway or yin long

 

[winkychevelle 10+ year member]

Ah ok. Got it. Yeah all I did was add the balancer to mine. I believe @KicktheSDbasshead was willing to sell some. I could be wrong. If I am, please correct me

Balancers are cheap and easy to install depending on the bars you use they are likely predrilled for the balancer if from a machine shop that does that kind of work often

 

[mat3833 10+ year member]

I don't think there really is a standard case since you can lay the cells out in so many different variations. If you do decide to diy Coventry industries likely has the bars you would need.

Nothing is wrong with lto other than min voltage to charge. At 5s instead of 6s max charge would be 14v which is why xs and d4s chose that configuration. Down side is alot of modern cars can spike higher than that.

You could add a voltage regulator to your current alt but you stated it was going to bug you cars computers. That leaves lifepo4 as the best option.

This is another alternative to headways and are arguably better cells. They just aren't as popular and finding bars may be more difficult.

4PACK LISHEN 8.5AH 30C 3.2V LifePo4 Prismatic Lithium Cells

4PACK LISHEN 8.5AH Battery has grown its annual production capacity up to 10GWh and has maintained the major market. Lishen prismatic lithium cell.

srikobatteries.com

I can totally regulate down. My car just doesn't want to run above 14.5 or so it varies on the temp. The car will happily start/run on anything above 10v but I get some misfires when voltage is that low if I get into boost. Above 14.3 or so and my MAF sensor reading goes wack and the ECU ads like 10 percent extra fueling. If I can keep my AGM and run the LTO charging at 13.8 it would be "ideal".

Ive still got to find out what alternator options I have. I need to start there and then decide on lithium chemistry and AH.

Matt

 

[HondaCRV03]

Balancers are cheap and easy to install depending on the bars you use they are likely predrilled for the balancer if from a machine shop that does that kind of work often

I bought the balancer from Amazon and the bars from project db. The 32ah bars ran me $100 shipped

 

[winkychevelle 10+ year member]

I can totally regulate down. My car just doesn't want to run above 14.5 or so it varies on the temp. The car will happily start/run on anything above 10v but I get some misfires when voltage is that low if I get into boost. Above 14.3 or so and my MAF sensor reading goes wack and the ECU ads like 10 percent extra fueling. If I can keep my AGM and run the LTO charging at 13.8 it would be "ideal".

Ive still got to find out what alternator options I have. I need to start there and then decide on lithium chemistry and AH.

Matt

I cannot say I would run agm with lto. Even regulating down 5s float voltage is 11.8 which will likely kill the agm.

This also means that once the alt cannot supply enough the voltage will drop down to 11.8v before holding solid.

This is why 4s headway is better than 5s lto. Sure lto can peak more amperage but it's at difficult to use voltages.

5s lto
11.8v float 13v rec charge 14v max
7.5v completely dead
6s lto
14.4v float 15.6 rec charge 16.8v max
9v completely dead.

4s headway
12.8v float 13.6v rec charge 14.6max
8v dead

Headways are going to be closer to maximum charge and above recommended charge voltage. You don't lose capacity until you go below recommended charge voltage and you don't lose a lot till you get really close to float charge.

You don't want to be below float charge as lithium hold voltage very steady but once they go below certain voltage the amperage drops flat. It isn't a nice smooth roll off like agm

 

[Firewalker]

Been watching this since I am in a similar boat right now. Got the 320 amp J&S Hairpin Alternator installed but still figuring out what to go with battery wise. Was gonna go with a XS Power D6500 up front and a super cap from XS in back. Right now even with a POS Walmart 55 dollar battery I charge at 14.7 and seen 15.1 a couple times. While playing I hit 12.9-13.4 then go right back up half a second later to 14.4-14.7. Also looked at the XS S5 Lithium for up front but I don't think it will take that charge. Plus I live in a area where it can get -20 to -30F below zero with wind chills -40 to -55F and that can last a couple days or 2-3 weeks. So gonna see how the OP handles this setup when done.

 

[winkychevelle 10+ year member]

Been watching this since I am in a similar boat right now. Got the 320 amp J&S Hairpin Alternator installed but still figuring out what to go with battery wise. Was gonna go with a XS Power D6500 up front and a super cap from XS in back. Right now even with a POS Walmart 55 dollar battery I charge at 14.7 and seen 15.1 a couple times. While playing I hit 12.9-13.4 then go right back up half a second later to 14.4-14.7. Also looked at the XS S5 Lithium for up front but I don't think it will take that charge. Plus I live in a area where it can get -20 to -30F below zero with wind chills -40 to -55F and that can last a couple days or 2-3 weeks. So gonna see how the OP handles this setup when done.

Don't do the xs 5s if you aren't consistently charging above 15v 6s lto isn't worth it. That said you likely can add a voltage controller and bump your voltage up a tad to get to 15-15.5v steady. I'm gonna assume a gm vehicle with the pcm controlled alt. It can be bypassed.

Depending on your maximum current draw agm you work.

320 amp alt - 20amp to run the vehicle
300amp remaining+86ah of battery
386amp of useful current at 13.8v
386×13.8=5326w maximum
though I like to be conservative and use the 10v figure
386×10v=3860w

 

[metalheadjoe 10+ year member]

I'm very happy with my JY Power HP40. Not cheap, but quick, easy install and effective. I wonder if I would need an HO alternator if i bought the battery first.

 

[winkychevelle 10+ year member]

I'm very happy with my JY Power HP40. Not cheap, but quick, easy install and effective. I wonder if I would need an HO alternator if i bought the battery first.

Looks like a decent lifepo4 battery. They list 13.8-14.8 as charge range which lines up well with 90% of the other lifepo4 cells out there. Only thing I don't like the the high voltage cutoff is 15.5v

I think it really should've been lower at least 15v. But I bet they set it high so gm vehicle that only spike up to 15.5v for 5min or less don't shut the battery down all the time. Those gm vehicles will settle to 14.4-14.6 rather quickly.