Lithium Batteries, Reposted

GreenMantis

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I copied this from another unrelated forum I posted it on, but it's still useful to anyone who wants to build a pack for themselves, so even if it's slightly out of context, here it is:

Regular Lithium Ion: Remember, these have the highest storage capacity, but they are DANGEROUS, and should only
be used with a protection circuit board, and should never be charged at more than 1C. These
also have the lowest discharge capacity, and will explode if charged or discharged too fast!

ICR LiCoO2 (Lithium Cobalt Oxide)

High Discharge Capacity: Better chemistry means these don't really need a protection circuit, and

IFR LiFePo4 (Lithium Iron Phosphate) -These have the longest service life of any battery ever made.
IMR LiMn2O4 (Lithium Manganese Oxide)
INR LiNiMnCoO2 (Lithium Iron Phosphate With Nickel/Manganese Oxide)

Primary cells (non-rechargeable)

ER Li-SOCl2 (Lithium Thionyl Chloride)
LS Li-SOCl2 (Lithium Thionyl Chloride)
CR Li-MnO2 (Lithium-Manganese Dioxide)
BR Li-(CF)x (Lithium-Carbon Monofluoride)
FR Li-FeS2 (Lithium-Iron Disulfide) - 1.5 to 1.8V "Energizer Ultimate"

The numbering usually refers to the size of the battery, a 14500 refers to "AA" size of 14mm x 45mm, a 18650 is 18mm x 65mm, and so on. At least with ICR, IMR, INR, and IFR types. So, "AA" size 3.7V primary cells are ER14500 or LS14500.

I'm going to add a breakdown on C rating.
There are a couple of factors to consider when trying to quantify capacity and discharge capacity. The "C" number is the minimum time the battery can be safely discharged completely in, quantified in fractions of one hour. So when they give you the capacity in mAh, they are telling you the 1C for the battery. So a 5Ah battery can be discharged completely if discharged @ 5A for one hour. This way you can multiply the mAh capacity by the C number to calculate the maximum sustainable discharge rate, in amps, with the time you can do it in given.
Let's say we have 2 identical looking packs, same size and weight, same capacity, 5Ah, but we'll make the first one a 20C and the other a 30C. The 20C battery can be discharged in (60/20=3) 3 minutes @ (20x5=100) 100A. The 30C battery can be discharged in (60/30=2) 2 minutes @ (30x5=150) 150A.

They don't usually give you the C rating with cylindrical cells, but you can do the math on them easily enough. Let's say we have a 2Ah IMR 18650 that gives a rating of 30A, just divide 30/2= 15C, so it can do 30A for 4 minutes. I think I did that right......
 
I copied this from another unrelated forum I posted it on, but it's still useful to anyone who wants to build a pack for themselves, so even if it's slightly out of context, here it is:

Regular Lithium Ion: Remember, these have the highest storage capacity, but they are DANGEROUS, and should only
be used with a protection circuit board, and should never be charged at more than 1C. These
also have the lowest discharge capacity, and will explode if charged or discharged too fast!

ICR LiCoO2 (Lithium Cobalt Oxide)

High Discharge Capacity: Better chemistry means these don't really need a protection circuit, and

IFR LiFePo4 (Lithium Iron Phosphate) -These have the longest service life of any battery ever made.
IMR LiMn2O4 (Lithium Manganese Oxide)
INR LiNiMnCoO2 (Lithium Iron Phosphate With Nickel/Manganese Oxide)

Primary cells (non-rechargeable)

ER Li-SOCl2 (Lithium Thionyl Chloride)
LS Li-SOCl2 (Lithium Thionyl Chloride)
CR Li-MnO2 (Lithium-Manganese Dioxide)
BR Li-(CF)x (Lithium-Carbon Monofluoride)
FR Li-FeS2 (Lithium-Iron Disulfide) - 1.5 to 1.8V "Energizer Ultimate"

The numbering usually refers to the size of the battery, a 14500 refers to "AA" size of 14mm x 45mm, a 18650 is 18mm x 65mm, and so on. At least with ICR, IMR, INR, and IFR types. So, "AA" size 3.7V primary cells are ER14500 or LS14500.

I'm going to add a breakdown on C rating.
There are a couple of factors to consider when trying to quantify capacity and discharge capacity. The "C" number is the minimum time the battery can be safely discharged completely in, quantified in fractions of one hour. So when they give you the capacity in mAh, they are telling you the 1C for the battery. So a 5Ah battery can be discharged completely if discharged @ 5A for one hour. This way you can multiply the mAh capacity by the C number to calculate the maximum sustainable discharge rate, in amps, with the time you can do it in given.
Let's say we have 2 identical looking packs, same size and weight, same capacity, 5Ah, but we'll make the first one a 20C and the other a 30C. The 20C battery can be discharged in (60/20=3) 3 minutes @ (20x5=100) 100A. The 30C battery can be discharged in (60/30=2) 2 minutes @ (30x5=150) 150A.

They don't usually give you the C rating with cylindrical cells, but you can do the math on them easily enough. Let's say we have a 2Ah IMR 18650 that gives a rating of 30A, just divide 30/2= 15C, so it can do 30A for 4 minutes. I think I did that right......
Not quite first any cell can be charged at 3c and some up to 5c.Witch means the 5ah cell/pack can be charged at 25 a if you have a charging system capable of it most consumer stuff wont.Next on the discharge side if a cell or pack is rated 20c it's peak discharge rate may be doubled so 40c or 200 a on a 5ah capacity.I currently have cells that have 45c nominal and 75c peak on a 5ah cell and they get charged at 10 a and are 3 going on 4 years old driving my ebike and still give 18 km run time at 5ah capicity they used to get 20 km when new so not bad.I have a charging system that shows the ma in while charging and the total time witch is 23 min at 10a fully charged.it shows 4,978 ma put in at end of cycle.
 
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