XOLTA BAT-79 User manual

Advanced energy storage system for
renewable energy and grid support applications
BAT-79 USER MANUAL
XOLTA OUTDOOR BATTERY ENERGY STORAGE SYSTEM
© 2021 by XOLTA

© 2021 by XOLTA
TABLE OF CONTENTS
1. Safety information and legal terms
1.1 Document purpose and structure ....................................................................................................................................3
1.2 Important safety Instructions ...........................................................................................................................................3
1.3 Actions in case of emergency situations ........................................................................................................................4
 1.4 XOLTAcertiedinstallers..................................................................................................................................................6
 1.5 Safedisposaloflithium-ionbatteries..............................................................................................................................6
 1.6 Disclaimer..........................................................................................................................................................................6
 1.7 Legal ..................................................................................................................................................................................6
 1.8 Copyright ...........................................................................................................................................................................6
1.9 Void of warranty ................................................................................................................................................................7
 1.10 Abbreviations ....................................................................................................................................................................7
XOLTA Battery Energy Storage System Overview
2.1 Introduction .......................................................................................................................................................................8
2.2 Hardware description .......................................................................................................................................................9
2.3 System safety ..................................................................................................................................................................10
2.3.1 Safety measures ..................................................................................................................................................10
2.3.2 InternalelectricalschemeoftheXOLTAoutdoorBESS ....................................................................................11
 2.4 Keyspecications...........................................................................................................................................................12
3. XOLTA Battery Energy Storage System
 3.1 Deliveryinspection..........................................................................................................................................................12
3.2 Location requirements ....................................................................................................................................................13
 3.3 Installationprocedure.....................................................................................................................................................13
  3.3.1Electricalrequirements........................................................................................................................................13
  3.3.2Installationoverview............................................................................................................................................14
3.4 System operation ............................................................................................................................................................18
3.5 Maintenance requirements ............................................................................................................................................18
4. XOLTA Battery System functionality
4.1 Operating modes .............................................................................................................................................................19
  4.1.1Maximizingsolarself-consumption ...................................................................................................................19
  4.1.2Externalcontrol.....................................................................................................................................................20
  4.1.3Gridvoltagesupport ............................................................................................................................................20
  4.1.4Loadfollowing......................................................................................................................................................21
 4.2 Sitecontrollerstatemachine .........................................................................................................................................21
4.2.1 SC States ..............................................................................................................................................................21
  4.2.2TransitionalSequences ........................................................................................................................................23
4.3 XOLTA outdoor BESS monitoring ...................................................................................................................................23
5. Web API
 5.1 WebAPI ...........................................................................................................................................................................24

© 2021 by XOLTA 3
1 SAFETY INFORMATION AND LEGAL TERMS:
1.1 Document purpose and structure
The purpose of this manual is to provide the user of the XOLTA Outdoor Battery Energy Storage System
(BESS) with an overview of system installation, functionality and operation.
The document is organized as follows:
Chapter 1 sets out important safety information, what to do in emergency situations and a list of abbreviations.
Chapter 2 gives a brief introduction to the XOLTA outdoor BESS system and describes its main features and key
 specicationparameters.SafetymeasuresandprotectionschemesusedintheXOLTAoutdoorBESSare
also described.
Chapter 3 deals with system installation, maintenance and location requirements. Liability limitations are also mentioned.
Chapter 4 describes currently available XOLTA outdoor BESS operating modes and operating states.
Chapter 5 provides a list of telemetry signals accessible via the Web API.
1.2 Important safety instructions
 TheXOLTAoutdoorBESSinstallationandservicingshouldonlybeperformedbyXOLTAcertiedinstallers.
 Inconsequence,XOLTAprovidesnoliabilityforpropertydamageorinjurycausedbysystemmodication
 orrepairsperformedbyunqualiedpersonnelorfailuretofollowthefollowingimportantsafetyinstructions.
The safety instructions have been divided into:
WARNING - indicates a dangerous situation which, if not avoided, could result in death or injury.
CAUTION - indicates a situation where damage to the equipment or injury may occur.
IMPORTANT SAFETY INSTRUCTIONS
Read the entire document carefully before installing or using XOLTA outdoor BESS.
RISK OF EXPLOSION:
Do not apply any external force to the XOLTA outdoor BESS.
Avoid physical damage to the battery. Keep the XOLTA outdoor BESS away from where it may accidentally
be physically damaged.
 DonotdisposeoftheXOLTAoutdoorBESSinre.
RISK OF FIRE:
 Keepsystemawayfromammableobjectsandheatsources.
Do not expose the battery system to temperatures in excess of 50°C.
RISK OF ELECTRICAL SHOCK:
There are high voltages present on AC and DC cables. There is a risk of death of serious injury due to electric
shock. Report any external cable/wire damage to XOLTA or local XOLTA system installer. Do not touch
uninsulated wires.

© 2021 by XOLTA
4
Never use a system if it is defective, damaged or broken.
Never attempt to disassemble, repair, modify the product or use it in any way other than as described in this
 manual.RepairsorreplacementofcomponentsmustonlybeperformedbyaXOLTAcertiedtechnician.
 NeverimmersetheXOLTAoutdoorBESSinwaterorotheruids.
RISK OF DAMAGE:
Do not expose the battery system to temperatures below -25°C or in excess of 50°C
Do not place any objects on top of the XOLTA BESS. It might lead to improper product operation or problems
with thermal management.
OTHER PRECAUTIONS:
The product should not be used for any purpose other than described in this manual.
Unpleasant smell might indicate electrolyte leakage from battery cell(s). In this case, switch the system off
and contact your XOLTA system supplier immediately. Ventilate the room if possible and avoid inhaling the odor.
The XOLTA outdoor BESS is heavy. Suitable lifting equipment is necessary.
Do not paint any part of the product.
For long term storage (longer than 1 month), the product should be charged to 40% SoC and then disconnected
from the grid. Observe warranty conditions.
The product must be disposed of according to local regulations.
1.3 ACTIONS in case of emergency situations
The XOLTA outdoor BESS is designed to be very safe. It monitors essential parameters of the battery system and
protects the battery from damage. The main battery safety measures are presented in Table 1.1 below.
Table 1.1:
List of main safety
measures in XOLTA
outdoor BESS
State of the art battery cells with excellent safety performance
State of the art battery management system (BMS) assuring over/under voltage and
over/under temperature monitoring for each individual battery cell
Redundant battery cut-off relay controlled by BMS
Temperature sensors monitoring battery system temperature
Active battery current control depending on battery cells temperature, voltage and state
of charge (SoC)
System diagnostics, error handling and automatic grid connection/disconnection
controlled by the site controller
Battery air humidity monitoring and condensation prevention system
AC and DC protective fuses

© 2021 by XOLTA 5
Despite all these built-in safety measures, emergency situations can still occur. In such emergencies, the
actions to take are as follows:
LEAKAGE
The battery pack might leak toxic electrolyte. Electrolyte is corrosive and odorous.
ACTION
• Avoid any contact with the leaking liquid or gas.
– In case of electrolyte inhalation - contact medical help.
– In case of electrolyte contact with skin - wash thoroughly with water and soap and contact medical
help.
– In case of electrolyte contact with eyes - rinse eyes with water for 15 minutes and contact medical
help.
– In case of electrolyte ingestion - force vomiting and contact medical help.
• Do not enter the room, if installed inside.
• Ventilate the room if possible.
• Contact your XOLTA system supplier.
FIRE
 Firemayoccurduetomechanicaldamageorexternalsourcesofheatandre.Hazardousfumessuchas
 carbondioxide,carbonmonoxideandhydrocarbonsareemittedduringbatteryres.
ACTION
• Disconnect the power from the battery system (if possible without getting too close to the battery and
without inhaling fumes).
 • Nevertrytoextinguishabatteryreyourself.Ifbatterycellscatchre,thenonlyqualiedreghting
  personnelwithappropriateprotectiveequipmentshouldattempttoextinguishthere.Keepawayfrom
  batteryreandcontactreghters.
 • Ifcomponentsotherthanbatterycellscatchre,thenABCorcarbondioxideextinguishercanbeusedto
  extinguishthere.
 • Keepawayfromthebatteryandcontactemergencyreghters.
IMMERSION IN WATER
Immersing the XOLTA outdoor BESS in water risks causing a short-circuit and damage to the battery system.
ACTION
• Do not try to access the XOLTA outdoor BESS.
• Disconnect the power (if possible without getting too close to the battery).
 • Neveruseaoodedbatterysystemagain.
• Keep away from the battery and contact your XOLTA system supplier.

© 2021 by XOLTA
6
DAMAGED BATTERY
Any sign of mechanical damage or abnormal behavior of the battery system or its peripheral components
should be treated with extreme caution.
ACTION
• Never use a damaged battery system again.
• Disconnect the power.
• Keep away from the battery and contact your XOLTA system supplier.
1.4XOLTAcertiedinstallers
XOLTA provides appropriate training to installation technicians for XOLTA systems.
 TheXOLTAoutdoorBESSmustonlybeinstalledandcommissionedbyXOLTAcertiedinstallers.Contact
 XOLTAforalistofavailableXOLTAcertiedinstallers.
1.5SafedisposalofLithium-ionbatteries
Lithium-ion batteries must be treated as hazardous waste and not be disposed of with regular waste.
A XOLTA battery which has reached the end of its functional life can be returned to the seller that originally
sold the battery or to the dealer of a new industrial battery.
1.6Disclaimer
We have taken every precaution to ensure that all information provided in this manual is correct and up to
 date.However,weassumenoresponsibilityfordamagetopersonsandpropertyarisingasaresultoffollowing
recommendations and/or procedures described in this manual. Furthermore, we assume no responsibility
for any infringements of rights of third parties which may result from the use of this manual.
1.7Legal
The system was designed to assure that an installed XOLTA outdoor BESS and all its associated function-
 alitiesbehavesafelyunderthepredenedoperatingconditions.However,please,readallsectionsdescribing
safety issues and precautions carefully before installation, operation, or performing service work on a XOLTA
outdoor BESS. Failure to do so could result in reduced system performance, damage to the system, personal
injury or even death.
1.8Copyright
This document and all information contained in the XOLTA User Manual are copyright 2021 by Lithium
Balance A/S. All rights reserved. Lithium Balance reserves the right to make changes to the products described
in this manual at any time without notice. This manual may be photocopied or otherwise distributed only to
the extent that is necessary for the correct operation and installation of XOLTA outdoor BESS.

© 2021 by XOLTA 7
1.9 Void of warranty
XOLTA does not assume any direct or indirect liability for any damage or loss caused if:
• The product covered is not continuously connected to the internet via LAN cable, meaning that XOLTA
cannot monitor the performance of said product;
• The product covered has not been stored, transported, set up or installed in an appropriate and professional
manner in accordance with technical standards and regulations, in accordance with the relevant installation
manual of the product or the instructions of XOLTA;
• The product covered has been operated contrary to its intended use or contrary to the instructions in the
relevant installation manual;
• The product covered was out of service for a continuous period of more than six months after the initial
installation due to the fault of the Purchaser;
• The product covered has not been serviced properly and professionally according to technical standards
or XOLTA’s maintenance instructions;
 • Theproductcoveredhasbeenexposed,eventemporarily,tovibrationsthateveninsignicantlyexceed
the usual extent of vibrations caused by transport and installation;
• The product covered has been improperly altered or otherwise tampered with by the Purchaser or any
third party;
• An overvoltage has occurred in the power grid to which the product covered is connected;
 • Theproductcoveredhasbeenexposedtoforcemajeure(inparticularlightning,re,earthquakeornatural
disaster) or harmful environmental conditions such as air pollution, salt water or sulphur corrosion;
NOTE! Always refer to the Terms and Conditions document delivered by XOLTA for warranty conditions.
1.10Abbreviations
Table 1.2:
List of abbreviations
used in this XOLTA
User Manual
BESS Battery Energy Storage System
BMS Battery Management System
BoL Beginning of Life
BPU Battery Protection Unit - a unit containing switches and fuses for battery protection
CAN Controller Area Network - Serial communication protocol developed by Bosch
CMU Cell Monitoring Unit of nBMS
DoD Depth of Discharge
EoL End of Life
ESS Energy Storage System
GUI Graphical User Interface
MCU Main Control Unit of nBMS
MODBUS Serial communication protocol developed by Modicon
n-BMS Battery Management System from Lithium Balance A/S
NTC NegativeTemperatureCoefcientthermistor
PCS Power Conditioning System
POR Power on Reset
PV Photovoltaic
SC Site Controller
SoC State-of-Charge
TCO Total Cost of Ownership
TMS Thermal Management System

© 2021 by XOLTA
8
2 XOLTA BATTERY ENERGY STORAGE SYSTEM OVERVIEW:
2.1 Introduction
The XOLTA outdoor BESS is a modular, cloud-connected multipurpose stationary energy storage system.
The BESS was designed for a wide range of ambient temperature conditions which makes it suitable for
outdoor installation without any additional enclosure. The system is designed for various operation modes
(applications) which will be further described in Chapter 4.
The main features of the XOLTA outdoor BESS are:
• PLUG AND PLAY: Simple installation and commissioning. The system requires grid connection, internet
and electric meter connections.
• ALL IN ONE: All components of the system are integrated into a single cabinet. This includes the battery
cells, the power conditioning system (PCS), the thermal management system (TMS), the battery management
system (BMS), the multi battery rack control system and the energy management system.
• OUTDOOR OPERATION CAPABILITY: The mechanical casing of the system was designed to be effective
up to enclosure rating IP55 (dust and water jet ingress).
 • MODULARITY:Thestoragesystempowerandenergycanbeexpandedandtailoredtospecicneeds.Intotal,
up to 32 XOLTA battery racks can be connected and operated in parallel providing up to 1MW and 2.5MWh.
• MULTIPURPOSE: The system is designed for various applications, from the integration of renewable energy
(e.g. increasing renewable self-consumption) up to various grid support applications (e.g. frequency and
voltage support).
• XOLTA CLOUD CONNECTION: The system is integrated with the XOLTA Cloud. It allows for system monitoring,
advanced control, data acquisition, and data storage.
• SAFETY: The system is designed to offer exceptionally high operational safety. For example, the system is
  ttedwithstate-of-the-artbatterysystems,multi-layerandredundantprotectionsystems,LithiumBalance’s
battery management system (BMS) which assure maximal system safety under various operating conditions.
 • LOWTOTALCOSTOFOWNERSHIP:Thisisachievedbyveryhighsystemround-tripefciency,lowstandby
losses, minimal operational and maintenance (O&M) cost and intelligent energy management.
• SITE CONTROLLER: This works as a multi battery rack control system and an energy management
system (EMS) which manages the entire XOLTA outdoor BESS. It provides charge/discharge power
management, monitoring to assure safe system operation, communication with all system peripherals
(e.g. the battery converter), data acquisition, communication with the XOLTA Cloud, system diagnostics
and error handling.
 • THERMALMANAGEMENTSYSTEM:Simpleandefcientparallelcoolingsystem.
 • PERIPHERALS:Possibilityofintegratingexternalenergymetersandother.

© 2021 by XOLTA 9
2.2 Hardware description
In this section, different hardware components of the XOLTA outdoor BESS are described. Figure 2.1 presents
the schematic drawing of the XOLTA outdoor BESS.
Each rack (battery cabinet) of the XOLTA outdoor BESS consists of eight serially connected battery packs
(as seen in Figure 2.1. All battery cells are protected by Lithium Balance’s n-BMS.
Figure 2.1:
Illustration of the
XOLTA outdoor
BESS hardware
components
Conv+
Conv-
Modbus TCP
L+N+PE
3L+PE
Ethernet
RJ45
Ethernet
RJ45
PCS
Conv+
Conv-
PCS
L+N+PE
3L+PE
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
Thermal management system
BESS Rack 1
BESS Rack N
+
-
-
+
+
-
-
+
-
+
+
-
+
-
-
+
BAT +
BAT +
PCS+
PCS-
PCS+
PCS-
BAT-
BAT +
Modbus TCP
Thermal management system
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
BMS Low
BMS High
+
+
-
-
-
+
+
-
-
+
-
+
+
-
-
+
BAT-

© 2021 by XOLTA
10
Figure 2.2:
Illustration of the
XOLTA outdoor BESS
BPU front view
Each XOLTA outdoor BESS has a battery protection unit (BPU). Figure 2.2 is an illustration of the BPU
consisting of a communication section and a power section.
The site controller is installed in the BPU and is connected to the XOLTA Cloud using the Ethernet port shown
in Figure 2.2. The Ethernet port ensures communcation between neighboring racks if operating in unison.
The site controller communicates with Lithium Balance’s n-BMSs via the CAN bus.
The DB9 Modbus port is used for communication with peripherals (e.g. energy meters).
The RJ45 port marked SPI is used for communication between the n-BMS MCU and the n-BMS CMUs (which
are located in battery packs). An additional DB15 plug is used for activation of the thermal management
system, sensing outdoor air temperature, LED diodes control and communication with the humidity sensor-
The Modbus TCP port is used for communication with the power conditioning unit (PCS) and communication
with neighboring racks if operating in unison.
The BPU is powered by single phase 230V AC and is protected by a 1.5A fuse located in the power entry connector.
2.3 System safety
2.3.1 Safety measures
The XOLTA outdoor BESS is protected by Lithium Balance’s state of the art n-BMS. The system
monitors essential parameters of the battery system (cell voltage, current, temperature) to
ensure safe operation. The n-BMS also monitors the battery main parameters, e.g. State of Charge
(SoC) and performs battery cell balancing to ensure maximal energy utilization and performance.
The XOLTA outdoor BESS is equipped with a battery protection unit (BPU) which protects the
battery and the inverter from conditions which can be detrimental to the BESS. It includes redundant
relays controlled by the n-BMS and redundant fast battery fuses.
In addition, in order to assure system longevity and safe operation (maintaining correct operating
temperatures), each of the XOLTA outdoor BESS battery packs is equipped with 12 temperature
sensors (two sensors per battery module). These give a total of 96 temperature sensors per battery
rack. This number of temperature sensors allows for quick detection of local temperature gradients
and thus ensures system safety and equal cell performance during the system lifetime. Furthermore,
temperature sensors are located on all battery safety-related PCBs
The thermal performance of the XOLTA outdoor BESS is also monitored by the site controller and
allows for power/current derating whenever the cell temperature or the ambient temperature is
outside a strictly determined range. The site controller also allows for converter error handling and
automatic connection/disconnection of battery racks.
NTC, LED,
thermal
management
B AT-
BAT+
CAN
Modbus RTU
Power
entry port
SPI
INV+
INV-
Ethernet
Modbus TCP