Six new BMS technologies has been introduced since 2020
1. Manages alternator cooling by controlling external in-line blower
NEW Feature introduced 2024
X2 BMS Pro has output to control external in-line blower based on temperature input from the alternator.
- Will monitor the temperature for one or two alternators.
- Will control in-line blowers, to cool the alternators.
- If a fault occurs so that the temperature rises and the alternator is at risk of overheating, the BMS Control alerts with flashing LED and high-yielding buzzers.
- Settings of different temperature by DIP switches.
2. X2-technology introduced 2020
..where the “X2” stands for management of two different batteries by combining the start lead battery (or aux) and the lithium battery into one system.
Benefits of an integrated lead-acid battery – X2 TechTM
- Backup battery and ability to supply power together with all chargers (when BMS is off / on)
- Pre-charge to avoid damage the charge relay
- Protects from load dump, from chargers connected to charge bus (i.e. avoid transient voltage spike.
- Supply controllers with input power; to manage wind and hydro generators and avoid damage when BMS disconnect the lithium battery.
- Allow chargers to show voltage when they are ON and thereby allowing X2 BMS sensing charge.
- All different marine alternators can easily be connected, including Yanmar and others, which require voltage at output.
- Charging with high current without energy loss (current will not pass any isolator, nor DC/DC device).
- Charge the starter battery via solar and other chargers when BMS is off (during winter storage).
- All chargers are able to charge all batteries included in the system.
- No isolator device needed between the batteries. (Lead battery combiner / voltage relay does not work with lithium and isolators have drawbacks).
- Power saving due to BMS will disconnect Charge relay when not charging (which also means power saving).
3. Charge Management System (CMS) introduced 2017
- Manage all chargers and disconnect charging including solar and alternator when battery is fully charged.
- Benefit of CMS is to avoid float charging which otherwise shortens the life of the lithium battery. Charging is reconnected automatically, only if certain discharge has taken place.
- The built-in Charge Management System (CMS) interrupts charging to the lithium battery when it is full and then continues to charge the lead battery (starter / Aux). CMS works fine with X2 BMS’ dynamic balancing which do not require the absorption charge.
4. Intelligent Dynamic Algorithm (IDA) to perform balancing, introduced 2021
- Will improve balancing during limited time periods when balancing can take place.
- IDA will boost balancing up to 5 times in comparison with other systems, which are unable to balance when chargers switch to float or are turned off.
When a marine charger switch from BULK to FLOAT and voltage drop from 14.2 V (28.4) to 13.5 V (27.0), the difference in cell voltage will disappear and no matter if cells are balanced or not. However, X2 BMS with Intelligent Dynamic Algorithm has the ability to continue balancing despite no cell delta.
5. Low Voltage Protection as the safest of all existing battery systems, introduced 2020
Low Voltage Protection (LVP) will cut off all discharging if the lowest cell is below threshold and after a time delay with several alerts and Pre-Alarm includes 2x buzzers.
- LVP at two different levels with different time delay.
- BMS will not trigger LVP-1 shut off due to voltage drop when battery is low and power consumption is very high. In such event BMS Control will alert the Pre-Alarm with a delay of 3 minutes.
The warning system makes it safe to utilize about 92% of the true capacity. When about 80% of lowest cell has been utilized, “Low Battery LED” starts flashing. When 93 – 95% of lowest cell has been utilized, “Pre-Alarm LED” starts flashing. The duration of Pre-Alarm / Low Battery is 27 minutes, where the final 2 minutes includes a Buzzer alarm.
The battery monitor (external) measures the current and makes an estimate of the state of charge (SOC) based on the capacity set in the battery monitor. Most often, the SOC calculation is not entirely true, because the battery monitor has not been synchronized for a while, but also because the capacity set is not the same as the true capacity of the lowest cell.
The difference between 80% of nominal capacity vs. 92% of true capacity can be as much as 50% more capacity utilization. A great pre-warning system based on cell status will increase capacity utilization by up to 50%.
6. Built-in pre-charge for the Load relay, introduced 2020 - improved 2024
Inrush currents into capacitive components are a key concern in switches and relays. When initially connecting a battery to a capacitive load, there is an inrush current as the input capacitance is charged up to the battery voltage. With large batteries and powerful loads (charger, inverter, alternator), the inrush current can peak 1000 A or more for just a millisecond.
In a X2 BMS controlled system, all chargers are always connected to starter or aux battery and will keep all capacitors* (chargers) pre-charged all the time. The X2-system eliminate need of pre-charge for the Charge Relay.
When pressing START button, BMS will be powered up during a limited period and Load relay will close with a delay of 5 seconds. During these 5 seconds, the Inverter, Multi (charger/inverter) and other capacitive loads at load side will be pre-charged. The current will be by-passed thru the power resistor before Load Relay closes and connects the lithium battery.
The pre-charge current is the highest in the market and will be sufficient for large inverters but also when parasitic current. The inrush current will be limited to 3.3 A.
*) Capacitive loads are all components that includes a coil, such as: Inverter, Multi/combo, alternator, motors as electric wind lass, winch and bow thruster. In most installations, capacitive loads will be chargers and loads, i.e. both load and charge relay must be protected by pre-charge.
The relay is bridged by a wire between two pins. This picture illustrates an arc created by a 3000 W inverter. If the system isn’t pre-charged, an arc will affect the relay on the inside in the same way.
The pre-charge power resistor is located inside the enclosure.