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Discussion Starter · #1 ·
I have an older cenntro metro, basically a club car 411

The batteries originally in my small electric truck are 120ah/3hr vrla gels (,8.64 kWh) 6 of them in series.

I temporarily have my everstart deeps cycles (109ah/20hr from my electric boat in the truck & its underwhelming in performance/distance

I get 10miles with the everstarts, 50 miles is advertised with the 120ah chiwee batteries that are bad.


Im trying to find to find the largest batteries i can afford that will get me back to the 50+ mile range.

Clubcar says its a 10kw/13.4hp motor.

Not ready to buy lithium setup due to price and headache of the built in bms on the machine.

I would be super happy to spend under 2k on new batteries.

Thanks!
 

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By now you should have noticed the inefficiency vs weight of FLA. THE only advantages they have is tolerance to charge processes and the generally 100% recycle.

Don't need to use the included bms, there are other options including none at all and associated caveats to them all.
I'm a none at all follower, and after 8 years still awaiting the nuclear meltdown everyone predicted back then.
I think CALB still sells cells, among others, and long term storage of half charged cells or packs means you can get deals from people abandoning their projects. You can sometimes get salvage auto packs.
 

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Discussion Starter · #3 ·
By now you should have noticed the inefficiency vs weight of FLA. THE only advantages they have is tolerance to charge processes and the generally 100% recycle.

Don't need to use the included bms, there are other options including none at all and associated caveats to them all.
I'm a none at all follower, and after 8 years still awaiting the nuclear meltdown everyone predicted back then.
I think CALB still sells cells, among others, and long term storage of half charged cells or packs means you can get deals from people abandoning their projects. You can sometimes get salvage auto packs.
Ill look into it alittle more, are you talking lithium ion /lifepo4?

Ive built plenty of lipoly packs over the years for rc planes but when i was looking at prices for 72v 200ah builds, bms and chargers the price was overwhelming.

Ill do some more research.
 

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In my case lifepo4, but lion can be used successfully if you are aware of the risks. Back when I got my volt pack they were 750 to 1000 USD, but the solar people suck them up as fast as they get wrecked anymore.
Over on flitetest, they are in awe at my 18 million mah 48s12p pack.
 

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LiFePO4 (or "LFP") cells are lithium-ion, as are the lithium-polymer cells (which are called that because they have a polymer electrolyte). LFP is often considered as a separate thing from lithium-ion cells with other electrode materials (NMC, NCA, etc), because the voltage range is lower and they're more thermally stable, but it's all lithium-ion.

Both LFP and other lithium-ion chemistries are available both new and salvage, but LFP is mostly new (because they are rarely used in production EVs), and the others are mostly salvage except in the little cylindrical format (18650). Salvaged cells from EVs - other than Teslas - are usually pouch cells, clamped into modules with their terminal tabs welded together, making them most practical to use in those original modules; the Tesla cells are glued together and have welded terminals, so they're only used as complete modules, too. Obviously salvaged is cheaper, and as a bonus when you salvage from a crashed EV you're getting cells suitable for EV use, rather than something that might only be appropriate for a low discharge rate.

One challenge in using modules salvaged from EVs is that all modern EVs run at a nominal battery voltage of 300 V or higher (usually 360 V), so when you only need 72 V you either get roughly 1/5th of a pack (so 1/5th of the original EV's energy storage, which is okay in this case if the original EV had 40 kWh or more) or you have to re-configure the modules internally. Nine or ten of the modules from a 40 kWh Nissan Leaf, or two modules from a Chevrolet Bolt, would give you enough energy in a volume that would be smaller than the lead-acid batteries.
 

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Deep cycle industrial lead units from excellent manufacturers will be 1/8 the price per usable Ah, at leadt in North America.

But LFP will be cheaper per year if you buy smart, last 20-30x more cycles. Double at least the energy density, also power output.

So long as your infrastructure ensures no "unexpected events" wipe out your investment in an instant.
 
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