The question is often asked by customers, especially by their  procuring departments as to why the individual batteries are not replaced instead or replacing new SYBT5 battery modules.
We do not recommend this as a solution as the SYBT5 is unique in regards to how it communicates with the system.  There is a circuit board inside the module that is calibrated to the individual batteries.  This provides the sophisticated battery management that the LX offers.
Installing new batteries into an SYBT5 would require someone to reprogram the module with the calibration code. The customer does not have this proprietary code nor the means to program it.
This is only done by Schneider Electric at our facilities when the battery modules are made.  It also ensures that the module has been properly programmed which avoids any adverse effects from a misconfigured SYBT5.
Because such reconditioned battery modules may not communicate with the UPS as would be the case after such a replacement, there are various issues which could impair system operation and fault alarms may appear.
In such cases Schneider Electric will not provide support for such batteries, or any faults that occur as a result of batteries which have been refurbished in this way.  If a site visit is required, such site visits would be billable regardless of contract on the UPS / Battery frame.
If a customer wishes to discuss this solution, it is important to impress on them all the consequences such a solution.
Conclusion:  We cannot approve replacement of the internal batteries for the SYBT5 by third parties, nor will we provide any work instructions. The XR battery system warranty would be invalid in such cases.   Unauthorized modification of a component assembly voids the system UL/IEC/CE rating.