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Hi so I am aware I think there are two types of batteries well 3

1 lead acid
2 Lipo4 ( or what ever value )
3 Lithium Ion

but what is the difference between the 2 and 3 please ? as I am trying to find a BMS and a charger for lithium ion and keep getting stuck.. only finding lipo4 stuff
 

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Hi so I am aware I think there are two types of batteries well 3

1 lead acid
2 Lipo4 ( or what ever value )
3 Lithium Ion

but what is the difference between the 2 and 3 please ? as I am trying to find a BMS and a charger for lithium ion and keep getting stuck.. only finding lipo4 stuff
Maybe, go read for awhile most the information can be found on wiki. LiFePO4 is a lithium ion chemistry. There are many li ion chemistries. There is also Nickel Metal Hydride. (Prius battery). There is also Lithium Metal batteries.
 

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Lithium is a very broad umbrella, dozens of chemistries including LFP.

The latter is nominal 3.2V, very long cycle life and one of the safest from a fire risk POV but not great energy density, still double that of lead though.

Those LI chemistries used in screen gadgets and for propulsion use cases are nominally 3.7V - charge setpoint often spec'd at 4.2V

often called "Li-ion" as opposed to LFP, higher energy density, much shorter lifespan, and very dangerous if not handled / cared for properly and proactively replaced as State of Health % declines in use.

These properties much more so in LiPo format packs as used in RC hobbies.
 

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LFP is a lithium-ion (Li-ion) chemistry.
Yes as I clearly stated.

But LTO and LFP are radically different from the other dozens of "lithium-ion" chemistries that have a nominal voltage of 3.7V

higher energy density etc etc, that are usually selected for propulsion packs

which are commonly referred to as "li-ion" as a shorthand by users to distinguish them from LFP

I agree this is bogus, all the above are in fact under the "lithium" or "lithium-ion" umbrella, but that fact is often elided in users' usage of terminology.

Examples of that "li-ion" (nominal 3.7V) category include LCO, LMO, NMC & NCA

and are found in prismatic / button / cylinder format with hard casing shells, as well as LiPo form with gelled electrolyte and flexible thin lightweight polymer / foil walls often requiring the pack builder to create a custom protective casing after assembly.

99% of the cell discussions online, users do not know, nor do they need to know which specific chemistry is used

Rather characteristics like tested power density vs energy density, maximum C-rate, continuous vs "peak" for short bursts, changes in temperature and ESIR under those conditions, cycle longevity under various use cases, etc are the usual parameters for decision-making in cell selection.
 
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