Managed Vs. Self-Managed Lithium-ion Batteries – Which is Best?

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In this blog, we’ll explore the advantages and disadvantages of both managed and self-managed batteries, providing insights to help you make an informed decision that aligns with your unique energy needs and preferences.

Batteries can be categorised into three groups: managed, self-managed and unmanaged. For the purposes of this article, we will be focusing entirely on managed and self-managed, as unmanaged batteries are highly volatile and not suitable for use within energy storage.

Managed Batteries

Managed batteries, like self-managed batteries, come with an integrated battery management system (BMS), offering the convenience of plug-and-play operation and seamless integration with power conversion equipment (PCE). In the realm of off-grid solar power systems, the unified integration of energy storage solutions is paramount. Imagine a system where every aspect, from energy conversion to battery management, works harmoniously to provide you with efficient, reliable power. This is where the concept of a managed battery truly shines. Let’s delve into managed energy storage, exploring how this combination offers a wealth of benefits for off-grid installers, homeowners, and businesses seeking the utmost in sustainable energy solutions.

Advantages of a Managed Battery:

  1. Efficiency and Automation
  • Quick to commission on site as battery and inverter parameters are often pre-programmed.
  • Energy-efficient operation due to intelligent management.
  • Automated charge and discharge control for optimised performance.
  • The direct communication between the PCE and storage ensure your systems components are optimised and always available under varying conditions such as intermittent load profiles, low state of charge and temperature.
  1. Remote Monitoring
  • Increased remote monitoring capabilities for real-time system performance checks.
  • The ability to troubleshoot and make adjustments without being on-site via compatible PCE.
  1. Battery Protection
  • Intelligent battery management to prevent overcharging and over-discharging.

Enhanced safety measures to extend the battery’s lifespan and performance.

Disadvantages of a Managed Battery:

  1. Limited Customisation
  • Limited ability to fine-tune settings and parameters compared to self-managed systems.
  • Some advanced users may desire more control over their system.
  1. Dependency on communications link
  • A managed battery requires a functioning communications link between chosen inverter platform and the battery system. Most systems will require a handshake between communications link to function. If this link is broken, there is potential for the battery system to go off-line.

Self-Managed Batteries

A self-managed battery, just like the previously discussed managed battery comes with an integrated battery management system (BMS) designed to optimize both safety and performance. Unlike a ‘managed’ battery, there is no external communication between the battery and the systems PCE.  Let’s explore the distinct advantages and potential challenges of self-managed batteries, shedding light on empowering the hands-on and simple approach to energy storage.

Advantages of Self-Managed Batteries

Simple Setup:

Self-managed batteries offer the advantage of being very simple compared to managed batteries. With no communication links required between PCE and battery, there is no risk of a failed communication link causing issues within your off-grid system. 

Disadvantages of Self-Managed Batteries

Expertise Required: Self-managing a battery system demands a good understanding of PCE programming and experience in off-grid solar installations.

Limited Remote Monitoring: Self-managed systems may lack the remote monitoring capabilities available with managed systems, making it challenging to detect and address issues without physically being on-site.

Inconsistent Performance: Without constant attention, a self-managed system may not consistently perform optimally under varying conditions.

Setting up a self-managed battery offers greater control and adaptability but requires a higher level of expertise and hands-on management. It’s essential to weigh the pros and cons carefully and consider your experience, available time, and the complexity of your off-grid solar system when deciding between self-managed and managed battery setups.

Is the Guardian Series a Managed or Self-Managed Battery System?

Regardless of your choice (managed or self-managed battery), the major advantage with the Guardian Series battery system is with the Swedish engineered Polarium batteries that allow you to set up the system as either a managed battery or self-managed battery. In addition, you also have the choice of Lithium Iron Phosphate (LFP), or Nickel Manganese Cobalt (NMC) lithium battery chemistries – there is no other battery manufacturer in Australia that offers this flexibility. It is no wonder Polarium batteries are trusted by critical infrastructure organisations across Australia for back up battery power when it matters most. Known for their reliability and efficiency, Polarium batteries are an excellent choice for sustainable off-grid energy solutions.

Supported Inverter Platforms (Guardian Series / Polarium Batteries)

Inverter / PCE Type

Managed

Self-Managed

Selectronic SP Pro

No Yes

SMA Sunny Island

YesNo

Victron Energy Multi-Plus / Quattro

YesYes

CE+T Power Sierra25

YesYes
Guardian LFPro Battery System

Is a Managed or Self-Managed Battery Better?

When considering which battery set up is best, it’s important to weigh up the advantages and disadvantages carefully. The decision should be guided by individual requirements, level of expertise, and budget constraints.

The key difference between a managed and self-managed battery is the “handshake” between the battery and the PCE. When there is communication (generally through CANBUS), the batteries are able to give the PCE greater detail on the real time condition of the battery and the system will self-adjust to manage this.

An example that highlights this is the state of charge (SOC). When dealing with an unmanaged battery, the power conversion equipment (PCE) relies on coulomb counting to estimate the SOC. However, this method is highly influenced by the C-rate, leading to significant inaccuracies and eventual SOC drift.

A managed battery will communicate the correct SOC with the PCE, allowing real time decisions on charge and discharge to be made with a high level of accuracy.

An unmanaged battery on the other hand may be a suitable choice if you prioritise simplicity and cost-effectiveness, as it eliminates the need for complex communication interfaces and can still provide basic functionality for certain applications.

Contact Solar Energy Australia for detailed information around managed and self-managed inverter integration.