Battery Management System For Lead Acid and Lithium Batteries


  • 14 x 12VDC outputs
  • 35A maximum output current
  • 20A solar input current
  • Lithium (LiFePO4) compatible

SmartConnect Ready

This product is specifically designed for and exclusively supplied in a range of Jayco recreational vehicles.


Preserve the health of your caravan battery

J35 Model B-L is an intelligent battery management system with a distribution system and a multi-stage battery charger. J35B-L model has been specially designed for Jayco and can be found on-board modern caravans and motorhomes.

Use J35B-L BMS for charging 12V Sealed Lead-Acid (SLA) batteries including valve-regulated lead-acid (VRLA) batteries, both absorbed glass mat (AGM) and gel batteries. This battery management system is also compatible with lithium batteries (LiFePO4). The power supply is able to deliver 35A  maximum to the battery and loads.

Charge your battery to the optimal charge level from AC mains, your solar panels, or from auxiliary (DC or vehicle power). A maximum DC charging current is 15 Amp. Multi-stage battery charger including bulk, absorption, float, and periodic boost charging modes to ensure long battery life. The J35B-L System supports up to 300W of panels with open circuit voltage between 18 and 28 VDC.

J35B-L keeps your battery healthy for a long time thanks to the multiple battery protection features, such as low voltage disconnect and storage mode.

Built in electronic fuses protect the loads. You can also use up to 14 outputs to connect your appliances, including hot water, water pump, lights, and more.

Get more out of the J35B-L intelligent battery management system by connecting it to accessories, such as battery monitors JControl or JHub. They will allow you get access to the monitoring your power supply status in a handy location. Moreover, when used with the ControlNode103, J35B-L is SmartConnect ready and allows monitoring multiple Bluetooth sensors via JHub app.

Product Specifications

Input Voltage Range: 240 VAC nominal, ± 10%, 50-60 Hz
Input Surge: < 40 A (cold start)
Output Current:  35A Continuous (load + battery current)

Factory Set Voltage:
13.65 V ±2% (Float voltage)
Output Ripple Voltage: < 150 mV
Over Voltage Protection: < 18 V
Over Current Protection: 35A to 38A (load + battery current)
Battery Current Limit: 15A max
Battery Connect: 10.8 ± 0.2 V

Low Voltage Disconnect:
10.8 ± 0.2 V
Battery Drain after LVD: < 8mA
Efficiency: > 83 %
Cooling Fan: Thermally controlled
Solar Input Current: < 20A
Solar Input Voltage: 15V to 25 V

Ambient: 0°C – 50°C
Weight: 2 kg
Dimensions: 282 x 203 x 65
Standards: Safety: IEC60335-2-29, IEC62109-1,UL458, CSA, C22.2 No.107-1, EMC: CISPR 14, IEC61000-3-2, IEC61000-3-3 Approvals: RCM, UL, cUL