Lithium battery applications were few and far between when Morningstar controllers became a standard used throughout the solar industry over the past decade. While lead-acid was predominant, we made sure to engineer advanced lithium features into our designs with an eye toward the future, including “fold back” circuitry for safe, effective charging under the extreme conditions our controllers frequently encounter.
Because of this forward-thinking approach, our long-established , TriStar MPPT, ProStar MPPT, SunSaver MPPT, TriStar-PWM, and ProStar Gen3 controllers are extremely well-suited to work with the latest l lithium batteries with programming we provide for that application. Furthermore, our new GenStar MPPT is an industry game-changer, with plug-in ReadyRail technology that lets a user seamlessly add a lithium ReadyBMS block to the controller for two-way communications and control.
Both the custom programming with our current line, and the new ReadyBMS capability with our new GenStar MPPT line, are part of our Energy Storage Partner (ESP) program. Encompassing over 20 of the leading lithium battery manufacturers, ESP provides the customized profile settings needed for seamless lithium integration into a new or existing project. In addition, several of the leading lithium brands in that program achieve 2-way communication and even closed-loop operation with a ReadyBMS used with our new GenStar MPPT controller. With either solution, using a lithium battery from our ESP program will result in a higher success rate when programming your controller.
Ultimately your battery manufacturer knows what’s best for their specific battery. If your battery is not on our ESP list, we strongly recommend you speak with your battery manufacturer to discuss their recommended charge settings and be sure to let them know you are using a solar charge controller. It’s helpful to review your controller’s Set Up Wizard in MSView or better yet, have the wizard open during your discussion to be sure to get all the information needed for the custom programming.
If your lithium battery bank has a battery management system (BMS) it must not be allowed to break the connection between the controller and the battery. The controller will not operate properly without the battery connected and can cause damage if the disconnect occurs while solar charging. The BMS can be prevented from disconnecting due to high battery voltage by setting the controller Absorption and HVD threshold slightly below the BMS High Voltage Cutoff threshold. Additionally, the controller will need to be custom programmed to disable equalization, disable temperature compensation and possibly limit the absorption and float stages.
For more information, please see our technical documents regarding lithium and other battery types:
https://www.morningstarcorp.com/lithium-batteries/
http://www.morningstarcorp.com/morningstar-best-practices-battery-chemistry/