Lead acid, included because the question of pairing an old bank with a new inverter comes up constantly. There is no BMS to talk to and the charge profile differs from lithium in every stage, so treat lithium settings as actively wrong here.
Published figures
- Usable capacity
- 20.6 kWh
- Capacity
- 428 Ah
- Voltage window
- 42.0 to 58.0 V
- Max charge current
- 85 A
- Max discharge current
- 200 A
- Comms
- none published
- Form factor
- Flooded bank
- Units in parallel
- 3
How many you need, by inverter
One pack accepts 85 amps. An inverter that can deliver more than that needs more than one, or the charge rate capped in settings. Both are valid, and the second one costs you charging speed on the short days when you need it most.
Communication
No document tracked here names a specific inverter for closed-loop operation with this pack. That does not mean it will not work. It means nobody has published the test.
Where the figures come from
Manufacturer documents: Rolls Battery documentation. Figures here should be read against the revision that covers your serial number, because manufacturers revise specifications without changing the model name.
Where to buy the Rolls S-480 48V AGM
Listings for the Rolls S-480 48V AGM plus the rack hardware and cabling a clean install needs.
Check price on AmazonServer rack for batteryBattery interconnect cablesAffiliate links. As an Amazon Associate this site earns from qualifying purchases, at no extra cost to you. Prices and stock change often, and a listing appearing here is not a statement that the pairing above is approved.
Questions people actually ask
How many Rolls S-480 48V AGM packs do I need?
One pack accepts 85 amps and holds 20.6 kWh. Match the pack count to your inverter’s charge current first, then check the energy. A Sol-Ark 15K at 275 amps would take 4 of them to charge at full rate, past the published parallel limit of 3, so that pairing charges at a capped rate.
Does the Rolls S-480 48V AGM do closed loop communication?
No, there is no communication port at all. Every pairing with this pack is open loop, and the inverter estimates state of charge from terminal voltage, which is unreliable through the middle of a LiFePO4 curve.
How many can I wire in parallel?
The published limit is 3 units.
Which inverters pair cleanly with the Rolls S-480 48V AGM?
None of the inverters tracked here clear all four checks with this pack. Most land on unverified because nobody has published the comms or surge figure, which is a gap rather than a fault.