My conversion to Lithium and Cerbo GX – Stefanie's experiences

Join the journey from traditional batteries to a modern Lithium system with Cerbo GX. Stefanie shares her learnings, practical tips, and how the upgrade improved energy management, safety, and comfort on board.

Skippers and adventurers may remember Stefanie's previous blog Sailing with Signal K, where she described how she connected the yacht's electronic systems to communicate with each other – and with her. During lockdown, Stefanie has been busy again – this time converting her yacht to Lithium batteries and exploring all communication possibilities with Cerbo GX, the heart of the new system.

Why Lithium?

• Almost double the usable energy with the same capacity
• High energy density and up to 70% weight saving compared to lead-acid batteries
• Efficient charging (99% efficiency)
• High charge and discharge currents – perfect for induction hob
• Low self-discharge and up to 5000 cycles
• Maintenance-free and makes gas on board unnecessary

Disadvantages of conversion

• High investment costs that only pay off over time
• More complex installation
• Cannot be charged below 5 °C
• Requires extensive safety solutions
• Old charging technology becomes partially unusable

Stefanie says: For us, the advantages outweighed the disadvantages. I know the technology and do the installation myself – it saves both time and money.

Energy on board

While sailing, Stefanie generates electricity via 510 Wp solar panels, supplemented by a 200 Wp portable panel in cloudy weather. When motoring, a Balmar 6-series 100A generator is used. More about the generator installation will follow in the next post.

Installation and components

Four Victron SmartLithium 12.8V 100Ah replaced the AGM batteries. The weight decreased from 33 kg per battery to 15 kg – a huge improvement for both space and handling.

All batteries are connected via Lynx Power In with cables of exactly the same length to avoid imbalance. The system is secured with ANL fuses and controlled via Cerbo GX and GX Touch 50.

Key components

• Victron MultiPlus 12/3000 – inverter and shore power charger
• Victron SmartSolar MPPT 150/35 and 75/15
• Victron Orion Tr-Smart DC/DC converter
• Victron Phoenix 12/375 for small AC loads
• VE.Bus BMS for cell protection
• Smart BatteryProtect for load and charge control

Full control with Cerbo GX

Cerbo GX acts as the brain of the system, providing a full overview via GX Touch 50 or remote access via the internet. All values can be monitored and controlled – including charging, temperature, tank levels, and NMEA2000 data.

Thanks to Victron Energy and Transwatt GmbH for the support. Follow Stefanie's blog at sailingtakumoe.de.