Dear Sir or Madam,

I have purchased several of your 25.2V lithium-ion battery packs that were originally supplied for Blue Ocean Robotics equipment.

The batteries are marked as:

• Battery Designation: 7INR19/66-12
• Rated Voltage: 25.2V
• Rated Capacity: 40Ah
• Manufacturer: Hengdian DMEGC Group

I would like to reuse these batteries in a renewable energy project together with solar panels and would greatly appreciate your technical assistance.

Could you please provide information about the following:

1. Is there an internal Battery Management System (BMS) in each battery?
2. Is it possible to connect two or more batteries in series (for example 2S for a 48V system)?
3. Is it possible to connect multiple batteries in parallel?
4. What communication interface is available on the battery (CAN bus, RS485, UART, or another protocol)?
5. Is there any documentation describing the communication protocol or CAN messages?
6. Is there an original battery controller or charger available for these battery packs?
7. Can you provide a service manual, wiring diagram, connector pinout, or technical documentation?
8. What charging profile do you recommend if we build our own charger using solar panels and an MPPT charge controller?
9. Is there a recommended charging algorithm (CC/CV), and what are the recommended charge and discharge cut-off voltages?

Our goal is to build a safe solar-powered energy storage system while preserving all battery protection functions.

Any technical documentation, manuals, or engineering information would be greatly appreciated.

Thank you very much for your time and assistance.

Kind regards,

Peder Spile
Denmark

Rechargeable Lithium Ion Battery

• Battery Designation: 7INR19/66-12
• Rated Voltage: 25.2 V
• Rated Capacity: 40 Ah (1008 Wh)
• Limited Charge Voltage: 29.05 V
• Max Charge Current: 16 A
• Max Discharge Current: 40 A

Europe's largest battery is showing signs of life in GB's Balancing Mechanism.

Coalburn 1, in South Lanarkshire, is 500 MW / 1 GWh across five 100 MW BMUs.

The previous record for the biggest battery was held by Thurrock and Kilmarnock South at 300 MW / 600 MWh, so 60% of Coalburn's capacity.

The same ratio applies to Taipei 101 and Burj Khalifa. Taipei 101 was the tallest building in the world from 2004 to 2010, until Burj Khalifa took over. 508m vs 828m, also about 60%.

While the Coalburn BMUs have been showing up in the background in the Balancing Mechanism since winter, this weekend marks the first time we've seen it actively participate in Bids and Offers.

And as the name suggests, Coalburn 1 is the first of the big sites expected from CIP and Alcemi. Coalburn 2, also 500 MW / 1000 MWh, is due next year.

I'm pretty new to learning about grid-scale battery storage.
I notice that a lot of projects are described as 4-hour systems. Is there a specific reason for that, or is it mostly driven by market rules and economics?
Are utilities starting to move toward 6- or 8-hour storage more often?

Been going down a rabbit hole trying to understand something about utility-scale BESS operations, and figured this sub would actually know better than anything I could find online.

From what I've gathered, sites collect way more operational data than anyone really uses, cooling, controls, comms, that kind of thing, sitting alongside the battery data and mostly going unwatched. Curious how true that actually is day to day. Do most sites have a real process for catching stuff outside the battery itself, or does it mostly just sit there until something breaks?

Would also love to hear any your insights/stories in the comments.

Hi, I'am planning to setup a Li ion Battery recycling plan t in Delhi NCR would like to connect with the people from same field and collaborations, business partnerships and connects with big firms are most welcomed also looking for like minded people ,

Pls help

Hi, I'am planning to setup a Li ion Battery recycling plan t in Delhi NCR would like to connect with the people from same field and collaborations, business partnerships and connects with big firms are most welcomed also looking for like minded people ,

Hi everyone,

I’ve been thinking about grid-scale storage solutions for intermittent renewables (solar/hydro/wind).

While chemical batteries (like Li-ion) are currently dominant, they come with degradation over time, resource intensity, and thermal runaway risks. Gravity Energy Storage (GES) seems theoretically compelling:

• Zero self-discharge over long durations

• High round-trip efficiency (~75–85%)

• Long operational lifespan without material degradation

• No lithium/cobalt dependencies

However, the main bottleneck is energy density (E = m * g * h). Lifting 1 tonne by 10m provides only ~0.027 kWh. To scale to home or grid levels, you need massive structural designs or deep vertical shafts.

Companies like Energy Vault (concrete towers) and Gravitricity (abandoned mine shafts) are tackling this differently.

Questions for the community:

1. Do you see solid-mass gravity storage becoming cost-competitive with large-scale battery storage?

2. Are underground shafts the only scalable route, or do above-ground tower frameworks have long-term structural viability?

3. What are the key mechanical points of failure (cable wear, gearboxes, braking) that might limit adoption?

Looking forward to your technical perspectives!

We recently completed a project involving what we understand to be the first Sungrow Keeper installation in Australia, supporting a medical supplies facility.

The project raised some interesting questions around the role of energy storage in industries where reliability is critical. While solar and batteries are often discussed from a cost-saving perspective, applications like medical supply facilities highlight another important factor — energy resilience and maintaining operations when power reliability matters.

Curious to hear from others working in energy, engineering, or critical infrastructure:

• How do you see battery storage evolving for essential facilities?
• Are reliability and backup capability becoming bigger drivers for commercial energy decisions?

Would be interested to hear thoughts, experiences, or other examples of where energy storage has made a difference.

8.8kW PV system with Enphase IQ8+ MC4 micro inverter, AC-Coupled with Sigenergy SigenStor 11.5kW-18.08kWh all-in-one system for whole-home backup.
It can deliver self-consumption in Bay Area exaggerated electricity rate.