Gel vs AGM battery: which to choose for UPS, solar and telecom
In short. For a UPS in an air-conditioned server room, choose AGM: it is built for short, high-current discharge. For solar systems, frequent cycling and rooms without air conditioning, choose gel or OPzV. They work from −40 to +65 °C, while AGM works from −20 to +50 °C. For 15–20 years of service, choose OPzV.
Both are sealed VRLA batteries; only the electrolyte holder differs
AGM and gel batteries are both VRLA (valve-regulated lead-acid). The electrolyte does not spill, and you never add water. Catalogues state gas recombination of 98 % or more and self-discharge up to 2 % per month for both.
The difference is how the electrolyte is held:
- AGM (absorbent glass mat): the electrolyte is soaked into a glass-fibre separator. The battery delivers high current fast.
- Gel: the electrolyte is thickened with silica into a gel. The battery handles deep discharge, heat and frost better.
Gel tolerates heat better; deep-cycle AGM gives more cycles
Figures are from the factory catalogues of the lines we supply: 12 V blocks for AGM and gel, 2 V and 12 V for OPzV. Service life is for float mode at 25 °C: the battery stays on charge all the time, as in a UPS.
| General-purpose AGM | Deep-cycle AGM | Gel | OPzV (tubular gel) | |
|---|---|---|---|---|
| Float service life | 5–10 years* | 5–6 years | 6–10 years* | 20 years |
| Cycles at 50 % discharge | not stated | 1 200 | 800 | 2 500 |
| Cycles at 80 % discharge | not stated | 600 | 450 | 1 500 |
| Operating temperature | −20…+50 °C | −20…+50 °C | −40…+65 °C | −40…+65 °C |
| Capacity range | 1–3 000 Ah | 7.2–250 Ah | 33–250 Ah | 100–3 000 Ah |
| Typical use | UPS, generator starting, security | solar, frequent cycling | solar, UPS, hot or cold rooms | solar, telecom, 15–20 years of service |
* Depends on capacity. AGM 12 V: 5 years up to 14 Ah, 6 years at 15–36 Ah, 10 years at 38–250 Ah. Gel 12 V: 6 years at 33 Ah, 10 years at 38–250 Ah.
“Gel always lasts longer” is not quite true: deep-cycle AGM gives more cycles than 12 V gel. Gel wins on temperature range and float life. For both cycles and years, choose OPzV with tubular plates.
Choose by task: AGM for UPS, gel or OPzV for solar, front-terminal AGM for telecom
| Task | What to install | Why |
|---|---|---|
| UPS in a server room, office or clinic with air conditioning | AGM; high-rate AGM for large UPS | Discharge is short (5–15 minutes) and needs high current. High-rate AGM gives 21–510 W per cell over 15 minutes |
| UPS in a room without air conditioning | Gel | Works up to +65 °C, AGM up to +50 °C |
| Solar system, daily discharge | Gel or deep-cycle AGM; OPzV for 15–20 years | The battery works in cycles, not in float |
| Telecom tower, telecom rack | Front-terminal AGM (12 years in float) | Terminals at the front: service without removing it from a 19” or 23” rack |
| Diesel generator starting | General-purpose or high-rate AGM | Catalogues list both series for generator starting |
| Substation, large 48–220 V bank | 2 V cells: OPzV, OPzS or 2 V AGM | Up to 3 000 Ah per cell, 20 years of service |
In solar, shallow discharge makes the bank last 2–3 times longer
A solar battery charges by day and discharges at night: about 365 cycles a year. Years below = catalogue cycles ÷ 365. This is an estimate, not a guarantee: heat and charge settings change it.
| Type | Nightly discharge | Catalogue cycles | ≈ years (estimate) |
|---|---|---|---|
| Gel 12 V | 50 % | 800 | 2 |
| Gel 12 V | 30 % | 1 800 | 5 |
| Deep-cycle AGM | 50 % | 1 200 | 3 |
| Deep-cycle AGM | 30 % | 2 500 | 7 |
| OPzV | 50 % | 2 500 | 7 |
| OPzV | 20 % | 6 800 | 18 |
A bank with spare capacity lasts 2–3 times longer, by this estimate. For daily deep discharge over 10–20 years, choose OPzV or OPzS.
Heat in Uzbekistan shortens battery life: keep the bank cool
All catalogue figures are given at 25 °C. An electrical room without air conditioning is much hotter in summer. The battery then lasts less. What to do:
- install batteries in a room with air conditioning or ventilation;
- do not place batteries in the sun or in a closed metal cabinet outdoors;
- for hot sites, choose gel, OPzV or special hot-climate AGM. By catalogue, hot-climate AGM lasts 10 years at 35 °C and works from −40 to +80 °C (100–180 Ah).
FAQ
Gel or AGM: which is better for a UPS?
In an air-conditioned room, AGM: it gives high current in a short discharge. If the UPS stands in a hot or cold room, choose gel.
Gel vs AGM for solar: which should I choose?
Choose a battery with a stated cycle life: gel, deep-cycle AGM or OPzV. General-purpose AGM is made for float mode, not for daily discharge.
What does VRLA mean?
Valve-regulated lead-acid. It is a sealed lead-acid battery with a valve. AGM and gel batteries are VRLA types. OPzV is also sealed, with gel electrolyte.
How long does a gel battery last?
By catalogue, 6–10 years in float at 25 °C, depending on capacity. In cycling, 800 cycles at 50 % discharge.
What is an OPzV battery?
A stationary lead-acid battery with tubular plates and gel electrolyte. It lasts 20 years in float and gives 2 500 cycles at 50 % discharge, about three times more than a standard gel battery.
We will select the battery for your task
Tell us what you power and how long it must run without the grid. We will calculate capacity and battery count. Price on request.
Catalogue: Batteries — GEL, AGM, OPzV.
For long outages: when the battery bank runs out, a diesel generator with automatic start takes the load: Diesel generators 50–10 000 kVA · Generator selection.
