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I have previously purchased a Delta Q QuiQ Charger, and I am now in the market for some lithium packs. I was looking at the LG Chem batteries, which have a nominal voltage of 60.8v and have a 45Ah capacity, so about 2.6kW.

The QuiQ charger is a 72v designed for lead acid, but the chemistry can be changed to lithium by changing the charging algorithm.

Does anyone know if the voltage difference will be a problem, as the LG batteries have a max voltage of around 67 volts?

I also understand there is a program on the computer where you can make your own charging algorithms. If someone has experience with these chargers, can you set a different target voltage in the program? Or can this be sent back to them to get modified to support that?

I have a feeling that it's likely not possible but I figured it's worth a shot asking, as it would save me a ton of time and hassle.
And if it isn't what would you recommend for a charger to charge these up in a reasonable amount of time?

Thanks!
 

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The 72V QuiQ charger algorithms start around 73V at the lowest cutoff algorithm, up to about 98V at its highest cutoff algorithm. You can't use it BY ITSELF with a 67V pack without severely overcharging it. You'll need a BMS to shut it off when you hit HVC on one cell. If you don't have a BMS, then you should not use this 72V charger, you should use a 48V charger (range from about 49V up to 65.5V), and charge to 65.5VDC.

Also, you can change the algorithms if you have the programmer, but you need the Lithium algorithms. They only include lead acid algorithms in the programming kit. I'm one of the few out there that program them for Lithium, and DeltaQ won't give them to you if you ask. I provide a programming service if you need. DeltaQ will make you go to Fullriver or somewhere else and they charge a ton.

You cannot make your own algorithm for that charger. The software allows you to load an algorithm from DeltaQ, but not to manipulate it in any way.
 

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I have previously purchased a Delta Q QuiQ Charger, and I am now in the market for some lithium packs. I was looking at the LG Chem batteries, which have a nominal voltage of 60.8v and have a 45Ah capacity, so about 2.6kW.



The QuiQ charger is a 72v designed for lead acid, but the chemistry can be changed to lithium by changing the charging algorithm.



Does anyone know if the voltage difference will be a problem, as the LG batteries have a max voltage of around 67 volts?



I also understand there is a program on the computer where you can make your own charging algorithms. If someone has experience with these chargers, can you set a different target voltage in the program? Or can this be sent back to them to get modified to support that?



I have a feeling that it's likely not possible but I figured it's worth a shot asking, as it would save me a ton of time and hassle.

And if it isn't what would you recommend for a charger to charge these up in a reasonable amount of time?



Thanks!
I can't speak to reprogramming that charger, but the voltage difference is a massive issue. Lithium cells never, ever go above the maximum voltage per cell when charging - not a single volt. In addition, smart lead acid battery chargers enter a float phase where the voltage will jump up significantly. The initial 5 volt difference is a huge deal, and hitting the float charge would be catastrophic.

Whatever you decide to do, don't use the charger as is.

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The 72V QuiQ charger algorithms start around 73V at the lowest cutoff algorithm, up to about 98V at its highest cutoff algorithm. You can't use it BY ITSELF with a 67V pack without severely overcharging it. You'll need a BMS to shut it off when you hit HVC on one cell. If you don't have a BMS, then you should not use this 72V charger, you should use a 48V charger (range from about 49V up to 65.5V), and charge to 65.5VDC.

Also, you can change the algorithms if you have the programmer, but you need the Lithium algorithms. They only include lead acid algorithms in the programming kit. I'm one of the few out there that program them for Lithium, and DeltaQ won't give them to you if you ask. I provide a programming service if you need. DeltaQ will make you go to Fullriver or somewhere else and they charge a ton.

You cannot make your own algorithm for that charger. The software allows you to load an algorithm from DeltaQ, but not to manipulate it in any way.
I have a 2.5kw Elcon charger in my MG that was originally programmed for lead acid. I considered just using my BMS to shut it off when it hit the cutoff voltage, but the extra layer of not-burning-my-house-down security if something went wrong was worth the wait and coin to get it reprogrammed.

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I considered just using my BMS to shut it off when it hit the cutoff voltage, but the extra layer of not-burning-my-house-down security if something went wrong was worth the wait and coin to get it reprogrammed.
This is the correct answer.

A charger with a fixed profile needs to be set at the 'normal' maximum charge voltage, the BMS only kicks in if there is a problem in the pack (single cell overvoltage, too low / high temperature, etc)

The other option is a CANbus controlled charger, usually sourced cheaply from scrapped EV's, or the still not so expensive Elcon TC Chargers.
 

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I do not recommend it, but it is possible to redneck-engineer this, set multiple independent/redundant HVD cutoffs to turn off an overvoltage charger below the pack's max safe voltage.

But getting close to 100% Full if you need that (the bank chemistry does not) will require pulse / delta-peak, all CC stage no CV charging,

letting V drop say 10-30min, then adding more Ah, multiple cycles until Resting V is at your SoC target.

Automating that would be a PITA and fragile, best done with you acting as regulator.
 

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I do not recommend it, but it is possible to redneck-engineer this, set multiple independent/redundant HVD cutoffs to turn off an overvoltage charger below the pack's max safe voltage.

But getting close to 100% Full if you need that (the bank chemistry does not) will require pulse / delta-peak, all CC stage no CV charging,

letting V drop say 10-30min, then adding more Ah, multiple cycles until Resting V is at your SoC target.

Automating that would be a PITA and fragile, best done with you acting as regulator.
And by the time you've done all of this work, you still have a huge fire risk that needs babysitting, even if it does end up being cheaper. I think I spent $60 or $70, including shipping, for the reprogram. I dont know what these other folks would charge, but if you cant find someone to do it reasonably, sell that charger and buy another. Its risky and a pain in the butt, best case.

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Came across some 270dc output PSUs, apparently widely used now in aviation and military gear.

Super as a "buss / backbone" voltage, especially where distances make wire gauge expensive,

only 15A gets you 4kW!

as long as you treat it with due respect, get a pro to help sign off on noob-level DIY wiring, that high is potentially instant-stop-your-heart deadly.

DC-DC step-down conversion units seem to be available pretty cheap?

_______
But really, the sweet spot for safely charging seems to be 48 nominal (up-to-60V), so much robust quality clean-output but cheap server / telecom gear is out there second-hand.

I think maybe building packs in that range, then quick-disconnect serial'ing them to get to 96, 144 etc volts is the way to go, just switch those blocks to parallel while charging.
 

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So are you thinking of using the 270v/15A and then using a DC-DC to bring it down to 48v?

I am definitely open to ideas, I haven't bought the battery yet, but do you think it'd be a better deal than $329 for a 2.6kW battery? That's like $130/kW. I ultimately want to be in the 144v range, how inexpensive do you think that method would be?
 

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Yes that's the idea, but it would be risky pioneering.

Best in practice to just spend the money to buy the proper OTS charger designed for that bank.

Which can often cost lots more than the bank, but hey it's just money.
 

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So are you thinking of using the 270v/15A and then using a DC-DC to bring it down to 48v?

I am definitely open to ideas, I haven't bought the battery yet, but do you think it'd be a better deal than $329 for a 2.6kW battery? That's like $130/kW. I ultimately want to be in the 144v range, how inexpensive do you think that method would be?
What motor and controller are you going to use? That will dictate your pack voltage requirement.

You can use a DeltaQ QuiQ with that 16s pack, just not the 72V charger. You'd need a 48V charger and have it programmed.

There are 96V DeltaQ QuiQ that go from like 96V to about 130VDC range with the algorithms I've got. Beyond that, you might need a different charger.
 

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I also have bought these LG A7 battery modules. I'm struggling to find a way to charge them collectively.

As they are 16S each already I was told I'd have to keep the battery pack configuration to 3P2S and finding a charger that could balance that pack would be very difficult. I may have to resort to charging each module individually. I do also have the additional balance harness for each module.

This is all new to me and I'm trying to prevent my investment from exploding or burning my house down! Any advice will be appreciated.
 

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I also have bought these LG A7 battery modules. I'm struggling to find a way to charge them collectively.



As they are 16S each already I was told I'd have to keep the battery pack configuration to 3P2S and finding a charger that could balance that pack would be very difficult. I may have to resort to charging each module individually. I do also have the additional balance harness for each module.



This is all new to me and I'm trying to prevent my investment from exploding or burning my house down! Any advice will be appreciated.
Is there some kind if extra board or circuitry in those batteries? I ask because I do not see why you would be limited in such a way on configuration.

The charger does not balance the cells. It only puts power into the battery pack. It doesnt know or care if the pack is in balance. That is the job of the BMS. The BMS will make sure that no cell is overcharged or overdischarged. It will also facilitate balancing the cells. As long as you can get to each cell somehow (like a connector with BMS leads for each cell), you can hook a BMS up to the cells. The BMS will turn off the charger if there is an issue. Otherwise the charger will just happily chug along until it reaches its maximum voltage and tapers off. Perhaps you can post the message you were given about the 3p2s configuration so that we can make sure things line up?

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Is there some kind if extra board or circuitry in those batteries? I ask because I do not see why you would be limited in such a way on configuration.

The charger does not balance the cells. It only puts power into the battery pack. It doesnt know or care if the pack is in balance. That is the job of the BMS. The BMS will make sure that no cell is overcharged or overdischarged. It will also facilitate balancing the cells. As long as you can get to each cell somehow (like a connector with BMS leads for each cell), you can hook a BMS up to the cells. The BMS will turn off the charger if there is an issue. Otherwise the charger will just happily chug along until it reaches its maximum voltage and tapers off. Perhaps you can post the message you were given about the 3p2s configuration so that we can make sure things line up?

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You're 100% correct. I misspoke. What I meant to say was that each of these modules has a BMS in it already (if I'm not mistaken) and I ordered an additional pigtail harness for each module that I was expecting would provide signal information about the condition of each of the 16 cells. I believe I wrongly assumed that power would need to be put through the harness as opposed to the terminals.

In the picture I've posted you can see the two small white plugs on each side of the middle connector. I believe those small plugs will provide the signal from each of the 16 cells to the main connector which is then output through the harness I bought to a larger or a "total system" BMS. That was my understanding but I may be wrong.


about the batteries being run in parallel, I reached out to several EV conversions shops and only 2 contacted me back. EVwest and AMPrevolt. Evwest advertises these batteries as being run in a 6S configuration only. Here is the email response I got from AMrevolt:

"Hi Matt,

Can’t dive in right this minute but I quickly scanned your email.

Sadly we don’t endorse putting those modules in parallel. Life would be SO much cooler (and cheaper and lighter) if we did, but because the BMS cannot see and control all it needs to when cells are in this configuration, it’s just not recommended without a lot of expensive mods and design time. We’ve been down this road a few times and always conclude to not do it. You might have seen others do it for short term races or whatev, but I know of no long term builds that attempted this.

Plus you mention building reliably for the next owner, so there’s another reason.

If you want to stick with these modules, I’d recommend using them in series with a high voltage motor. Unfortunately that rules out HPEVS and Netgain’s Hyper9 unless you use like only 2-3 LG modules.

This is kind of major, so wanted to let you know asap."


I was really hoping to utilize all 6 modules I purchased in a 3S2P configuration so that I could run the new 144V hyper9 motor and get twice the Ah rating.

Sadly, I just don't know what I really need to make this all work. I feel like I bit off more than I can chew and I'm trying to avoid just shipping this off to EVwest to be built by them. I'd like to do it myself but I keep running into issues over major hurdles that everyone else seems to see but me.
 

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Seems like a coulda shoulda woulda situation.

If you can't

1. find & pay a specialist in these cells to mod them properly, or

2. DIY strip out / bypass their BMS, hook the bare cells up as you like and replace its protections with your own or OTS gear,

then it looks like you're SOL and need to try to get as much of your money back on those packs as possible, and start off from scratch with different packs,

this time really doing due diligence before spending the money.
 

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I have these batteries and intend to configure as 2S5P with zeva BMS and hyper9 , the connectors are simply a tap to each cell + 2 temp sensors. The zeva BMS has a setting to define the number of parallel strings.
 

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Are you set on the hyper9? It's pretty darn pricey for 88kw peak... perhaps other options would work?

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