Quote:
Originally Posted by oil pan 4
It might be cheaper to build up 11 or 12 cell stacks of NiMH batteries.
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The Li Fe Phos (not the same as regular Li Po, see descriptions below) can be discharged at a very high rate compared with NiMH.
The 2.5 AH, Li Fe Phos cells have Maximum Continuous Discharge 70A.
Two sets in parallel would have max cont discharge of 140A and would power your car's starter motor.
I found a 4.5AH NiMH with Standard Discharging Rate: 4.5A
I found a 3.5AH NiMH with Max.Discharging current 3.5A
NiMH rechargeables
You could look here for comments/discussion:
Lithium batteries v/s NiMH batteries the Debate! Battery technologies | V is for Voltage electric vehicle forum
Below is a quote from a r/c hobby message board post
RC Groups - View Single Post - Lipo vs. A123 vs. LiIon vs. LiFePO4 vs. NiMH:
Lithium-Polymer (LiPo) - this was an evolution of Li-ion that is used often in the RC hobby today. The packs are flat and somewhat flexible (but don't bend them, it can damage them), though sometimes can be contained within a hard case. They have a large amount of energy that can be delivered at very fast rates (high current) they recharge relatively quickly and are lightweight. They are also relatively easy to damage, both physically and electrically, and can catch fire and explode if mistreated (any battery can, but LiPos can be violent when they go). These are 3.7 volts per cell.
Lithium Iron Phosphate (A123/LiFePO4) - A123 is a brand-name for the LiFePO4 cells. These are technically Lithium-Ion batteries, but they're a specific subset, so they are considered different. They're generally available in two cell sizes in our hobby, 1100 mAh and 2300 mAh. They are round cells with hard cases. Because of the different chemistry, they are slightly heavier and slightly lower voltage than a comparable LiPo pack. However, they are showing to be much more durable than a comparable LiPo, being able to take more physical as well as electrical abuse. They can be discharged/recharged at higher rates than LiPos. These are 3.3 volts per cell.
Nickel Metal-hydride (NiMH) - slightly older technology that uses a completely different chemistry than Lithium-based batteries. It's heavier and less energy dense than LiPo, and ~1.2 volts per cell. You'll find these in hard round cases. They can be discharged/recharged relatively quickly. They are also quite durable and have been used for years, and still used today.