---
title: "FoxESS ECS2900-H7 vs Deye GB-L20 - Battery Comparison | ComparePV"
description: "Compare FoxESS ECS2900-H7 vs Deye GB-L20 side by side: usable energy, round-trip efficiency, power, cycle life and the full specification."
source: "https://comparepv.com/compare-batteries/fox-ess-ecs2900-h7/gb-l20"
updated: 2026-01-11
---

# FoxESS ECS2900-H7 vs Deye GB-L20

GB-L20 leads on the differences that matter

The largest is usable energy: 0.26 kWh apart. 8 of 18 comparable parameters are identical, with 15 more left out because at least one datasheet does not publish them.


## The two batteries


| Attribute | A | B |
| --- | --- | --- |
| Battery | [FoxESS ECS2900-H7](https://comparepv.com/battery/fox-ess-ecs2900-h7) | [Deye GB-L20](https://comparepv.com/battery/gb-l20) |
| Manufacturer | FoxESS | Deye |
| Usable energy | 18.14 kWh | 18.4 kWh |
| Cells and voltage | LFP HV | LFP HV |

[See 21 FoxESS offers](https://comparepv.com/offers?manufacturer=foxess&product_type=battery)

[See 44 Deye offers](https://comparepv.com/offers?manufacturer=deye&product_type=battery)


## Where they differ

Ranked by how much the difference matters, not by datasheet order.


| Parameter | ECS2900-H7 | GB-L20 | Difference |
| --- | --- | --- | --- |
| Usable energy | 18.14 kWh | 18.40 kWh | 0.26 kWh apart |
| Max system capacity | 20.2 kWh | 24.5 kWh | +4.4 kWh for GB-L20 |
| Nominal energy | 20.16 kWh | 20.45 kWh | 0.29 kWh apart |
| Nominal voltage | 403 V | 512 V | 109 V apart |
| Weight | 228.3 kg | 214.0 kg | -14.3 kg for GB-L20 |
| Weight per kWh | 12.6 kg/kWh | 11.6 kg/kWh | -1.0 kg/kWh for GB-L20 |
| Max operating temperature | 55 °C | 60 °C | +5 °C for GB-L20 |
| Modules per stack | 2-7 | 2-6 | 2-7 vs 2-6 |
| Operating voltage | 340.2-459.9 V | 166.4-700 V | 340.2-459.9 V vs 166.4-700 V |
| Dimensions | 950x570x380 mm | 1310x540x385 mm | 950x570x380 mm vs 1310x540x385 mm |


## Every compared parameter


| Parameter | ECS2900-H7 | GB-L20 |
| --- | --- | --- |
| Usable energy | 18.14 kWh | 18.40 kWh |
| Nominal energy | 20.16 kWh | 20.45 kWh |
| Depth of discharge | 90 % | 90 % |
| Max system capacity | 20.2 kWh | 24.5 kWh |
| Modules per stack | 2-7 | 2-6 |
| Continuous discharge power | - | 20.48 kW |
| Continuous charge power | - | 20.48 kW |
| Peak discharge power | - | 25.60 kW |
| Power per kWh | - | 1.11 kW/kWh |
| Round-trip efficiency | 95.0 % | - |
| Cycle life | 6000 cycles | 6000 cycles |
| Cycle test depth | 90 % | - |
| Capacity at end of life | - | 70 % |
| Self-discharge | - | - |
| Voltage class | High voltage | High voltage |
| Nominal voltage | 403 V | 512 V |
| Operating voltage | 340.2-459.9 V | 166.4-700 V |
| Cell chemistry | LFP | LFP |
| Active cell balancing | - | - |
| Thermal management | - | Yes |
| Inverter | None (battery only) | None (battery only) |
| Inverter power | - | - |
| Grid connection | - | - |
| Backup power | - | - |
| Weight | 228.3 kg | 214.0 kg |
| Weight per kWh | 12.6 kg/kWh | 11.6 kg/kWh |
| Dimensions | 950x570x380 mm | 1310x540x385 mm |
| Ingress protection | IP65 | IP65 |
| Outdoor-rated | Yes | Yes |
| Min operating temperature | -20 °C | -20 °C |
| Max operating temperature | 55 °C | 60 °C |
| Warranty | - | 10 yrs |
| Warranted throughput | - | - |


## Related comparisons

- [FoxESS ECS2900-H7 vs Dyness Tower Pro TP19](https://comparepv.com/compare-batteries/fox-ess-ecs2900-h7/dyness-tower-pro-tp19) - 13 differences, the largest is cycle life
- [FoxESS ECS2900-H7 vs Deye GB-SL-EU (5 modules in series)](https://comparepv.com/compare-batteries/fox-ess-ecs2900-h7/gb-sl-eu-5-modules-in-series) - 11 differences, the largest is usable energy
- [FoxESS ECS2900-H7 vs Solplanet Ai-HB 200A](https://comparepv.com/compare-batteries/fox-ess-ecs2900-h7/solplanet-ai-hb-200a) - 10 differences, the largest is usable energy
- [Deye GB-L20 vs Deye BOS-G20](https://comparepv.com/compare-batteries/gb-l20/bos-g20) - 9 differences, the largest is max system capacity


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Source: https://comparepv.com/compare-batteries/fox-ess-ecs2900-h7/gb-l20

Not in this file, on the page: a written summary generated on request.