Decreased capacity, voltage, and life and increased IR losses and heating are seen with higher discharge current rates, along with a more rapid decrease in voltage during the discharge. If we discharge keeping cutoff voltage constant, lower current rate would have additional capacity available, above that cutoff voltage, than higher one. Discharge rates are commonly specified as multiples of the C rate, which is the current that will discharge the battery to the cutoff voltage in one hour. 1C rate means battery will be discharged completely in 1 hr by the discharge current.

=== Charge Current Rate ===

=== Continuous or Intermittent Discharge ===

When a battery rests after discharge, voltage recovery happens due to certain physical and chemical changes happening. Thus, the voltage of a battery that has dropped during a high-rate discharge will rise after a rest period. This improvement is generally greater after discharge at higher currents and also is dependent on the end-of-discharge voltage, temperature, and the length of the rest period.

=== Charging Voltage and Voltage Regulation ===

=== Vibration and Shock ===

In this method, battery is charged with a constant current until voltage reaches the end-of-charge(EOC) voltage. Thereafter, charger switches to a constant voltage charging, where the charging current falls with time. The battery is said to be charged when the charging current drops to a predetermined limit. This is the preferred mode for charging Li-ion batteries.

== Battery Discharging ==

Significant advances have been made in the cathode materials and electrolytes for Li-ion cells and batteries. Several new cathodes with high specific capacity approaching 250 mAh/g, coupled with high voltage and improved thermal stability have been identified. Likewise, several new electrolytes for enabling operations at -60 °C have been demonstrated. These advances are expected to results in advanced lithium-ion cells and batteries with high specific energy and wide range of operating temperatures, as desired in future space missions. <ref name = "ieee"/> However, the polymer li-ion cells have an additional problem with electrolyte leakage under abusive conditions.<ref name = "nasa">https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090023862.pdf</ref>

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A PTC (Positive Temperature Coefficient) switch can also be used to prevent short-circuiting by inhibiting high currents. As temperature increases above a limit, material resistance faces a large increase and being reversible they cycle back to conductive state when we have normal condition again.

CIDs (Current Interrupter Devices) can prevent further charging of a battery until internal pressure(of battery) is alleviated. These devices prevent venting of hazardous electrolytes and bursting due to buildup of high pressures.<ref name = "nasa2">https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150020899.pdf </ref> However, both PTCs and CIDs may fail when exposed to high voltages due to other failures. The use of bypass diodes is recommended to prevent these failures.<br \>

Certification of the crimp is critical for ensuring that individual cells will not leak after launching.<ref name = "nasa2"/> Cell terminals need to be protected from contact with other conductive surfaces. <br \>

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==References==