Internl resistance of batteries

Does anyone know what the internal resistance of turnigy multistar 22.2v 6s 16AH is? Also, how does internal resistance effect the efficiency of the ebike? Like range specifically. Thank you

RonnieBrowen2106 said:

Does anyone know what the internal resistance of turnigy multistar 22.2v 6s 16AH is? Also, how does internal resistance effect the efficiency of the ebike? Like range specifically. Thank you

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The effect of internal resistance on endurance becomes noticeable when, and only when, the battery is being discharged at close to its practical capacity. In the case of that specific battery, discharge at 2C should make little difference in the total watt-hours you can extract versus discharging at 1C or less.

At e-bike power levels, heat buildup due to internal resistance is probably a more critical issue than reduction of range. If you're running that close to your max range, you're beating your battery up anyway.

Ok. Thanks Chalo.

Brand new, mine were 11-14mOhm ACIR. That is direct to the battery, no cables/connectors. Site claims <3mohm per cell, so anything under 18mOhm is truthful.

I have a 1 week old 4S, or a 18 month old 6S (about 100 partial cycles) if you want an exact measurement.

I'm sure at some point, one cell measured that low IR. But with hobby king, the rule of thumb is take the c rate they claim, and to have a pack that runs cool and happy, cut that by 3/4. So a 20c pack, discharge it at 5c rate. ( that's 5 x 16 ah for your pack, so 60 amps is ok, more if the c rate is more than 20)Then you can run it well for its lifespan, even after it gets a bit older, and has worse IR.

This is why a 5 ah 20c pack gets all hot, if you run 40 amps. Its because they overstate the IR of it, and thus, the c rate.

IR increases as a pack nears 100% discharge, so go easy on that last two miles.

Awsome thanks for all the Awsome info. I have saved a video off YouTube from an ES member on Lipo Care and Precautions. He had a "proud sponsor of endless sphere shirt." It was a nice shirt.

Hello,

I didn't want to open new topic, because I think my question concerns internal resistance of cell.

So, why does the maximum charging current (or power) of lithium-ion battery packs differs from discharging one if the internal resistances are almost the same for charging and discharging (hysteresis is also neglible)? For example, Saft superphosphate cell could be discharged with as much as 1500 A, but charging is restricted to only about 150 A.