# Solar battery Trojan 31-AGM 12V 100Ah AGM ![Solar battery Trojan 31-AGM 12V 100Ah AGM](https://baterias.com/687-home_default/battery-trojan-31-agm-12v.jpg) > Trojan 31-AGM solar battery 12V 100Ah AGM. Dimensions 341Γ—173Γ—233 mm. Designed for PV systems with daily cyclic loads. **Category:** [Batteries for Solar Applications](https://baterias.com/gb/batteries-for-solar-applications) β†’ [TROJAN](https://baterias.com/gb/trojan) - **Canonical URL**: https://baterias.com/gb/battery-trojan-31-agm-12v - **Language**: en-GB - **Brand**: TROJAN - **Reference**: BCOM-TROJAN-31-AGM - **EAN**: 8404653001537 - **MPN**: 31-AGM - **Stock**: Out of stock ## Technical specifications | Feature | Value | |---|---| | Brand | TROJAN | | Reference | 31-AGM | | Model | TROJAN AGM | | Voltage (V) | 12 V | | Largo | 341 mm | | Ancho | 173 mm | | Alto | 233 mm | | Peso | 31 kg | | TecnologΓ­a | AGM | | Terminal type | 6 | | Capacity (C20) | 100 Ah (c20) | | Capacity (C5) | 82 Ah (c5) | ## Quick description **Trojan 31-AGM 12V 100Ah** is a solar battery designed for PV systems with daily charge/discharge cycles. Tolerates extreme temperatures well, with low self-discharge during winter shutdowns or between stays at vacation homes. ### Why this solar battery? - **Designed for solar systems** optimised for daily charge/discharge cycles - **Handles extreme temperatures** in technical rooms or outdoor installs - **Minimal self-discharge** when left idle over winter or holidays πŸ”Œ Voltage 12 V ⚑ Capacity 100 Ah C20 πŸ“ Dimensions 341Γ—173Γ—233 mm βš™οΈ Technology AGM βš–οΈ Weight 31 kg 🏷️ Model TROJAN AGM ## Description ## Solar battery Trojan 31-AGM 100Ah 12V 12*V* Voltage 100*Ah* Capacity 31*kg* Weight The **12 V**, **100 Ah** **Trojan 31-AGM** solar battery with AGM technology is designed for off-grid photovoltaic installations and storage systems. Measuring 341 Γ— 173 Γ— 233 mm, it is the direct replacement for off-grid PV systems fitted from the factory with a 100 Ah battery of this format. - AGM: faster recharging and better cycle resistance than a conventional battery. - Low self-discharge during the darker months. - Maintenance-free in off-grid installations. - Compatible with common MPPT and PWM controllers. ### What the Trojan 31-AGM is for With 100 Ah, the Trojan 31-AGM stores the energy from your panels for the night and cloudy days. Check that it matches your current battery in dimensions, terminals and hold-down: this reference has a weight of 31 kg and 6 terminals. ### Technology inside the Trojan 31-AGM The 31-AGM is one of the Trojan references for this type of use; it shares the same manufacturing and quality-control criteria as the rest of the brand's catalogue. In an AGM battery the electrolyte is absorbed in glass-fibre separators: there is no free liquid, it cannot spill and it can be mounted at an angle. That construction lowers internal resistance, speeds up recharging and multiplies cycle life compared with a conventional battery. ### Will it fit your current battery tray? The Trojan 31-AGM is made in the 341 Γ— 173 Γ— 233 mm format and weighs 31 kg. It uses 6 terminals, the system that anchors and connects it in the vehicle. For a direct replacement, the current battery tray must accept these dimensions and the same terminal layout; otherwise adapters will be needed or the hold-down will change. ### Why choose Trojan batteries Founded in 1925 in California, Trojan invented the golf cart battery and remains the standard in deep-discharge applications that demand thousands of cycles. We guarantee that every Trojan arrives new, charged and with the manufacturer's full warranty. ### Usage and maintenance tips Size the installation so as not to discharge the battery more than 50% daily and set the controller to the battery technology. In the darker months, check the voltage periodically and avoid full discharges. ### Manufacturer's warranty The Trojan 31-AGM comes with the **manufacturer's official warranty** against manufacturing defects. If it fails through a defect within the warranty period, we replace it at no cost to you. ### Shipping, delivery and returns Same-day dispatch from our warehouse for in-stock orders placed **before [[ks:cutoff]]**: 24-48 working hours in mainland Spain and Portugal, 3 to 5 days in the islands and the rest of Europe. Returns are accepted for **[[ks:return_days]] days** if the battery has not been used (free collection on the Iberian mainland). You will receive tracking by email. ## Frequently asked questions ### Is the Trojan 31-AGM an AGM battery and what are the benefits of AGM? Yes. The 31-AGM from Trojan uses AGM (Absorbent Glass Mat) technology: a sealed lead-acid battery where the electrolyte is absorbed in a glass-fibre mat. It withstands more charge/discharge cycles than a conventional one, handles heat better and is the required technology for devices with advanced Start-Stop and regenerative braking. Expected lifespan: 5-8 years under normal conditions. ### How is the Trojan 31-AGM battery installed in the vehicle? In most devices it fits in 15-30 minutes with a 10 mm wrench; if the battery is under the seat or in the boot the time can double. See the step-by-step guide on this page. Quick summary: 1) switch off the engine and remove the key; 2) locate the original battery (engine bay, boot or under seat); 3) disconnect the negative (βˆ’) terminal first, then the positive (+); 4) loosen the hold-down clamp and remove the old battery; 5) fit the new one in the same orientation β€” match the polarity shown on the product sheet; 6) connect the positive (+) first, then the negative (βˆ’). On devices with Start-Stop or BMS, register the battery via OBD so the alternator applies the correct charging profile. ### How long does the Trojan 31-AGM battery last? Expected lifespan of the Trojan 31-AGM is 5 to 8 years in mild-climate device use with Start-Stop. In cold regions it drops slightly due to cold-start stress; in very hot regions it also drops because of electrolyte evaporation. To extend its life: avoid deep discharges (headlights on with engine off), have the alternator checked yearly, and keep the battery clean and properly secured. ### What are the dimensions of the Trojan 31-AGM battery? Dimensions (length Γ— width Γ— height) are 341Γ—173Γ—233 mm β€” also written as 341x173x233 mm β€” following the European DIN standard. Always measure the space in your device before buying: even one extra millimetre can prevent the hold-down clamp from closing. The height shown includes the terminals. ### What are the equivalents of the 31-AGM model? Directly interchangeable batteries (same dimensions, same polarity, same Ah and CCA) are the OEM equivalents from leading brands: Bosch, Tudor, Exide and, depending on the model, Banner or Yuasa. Exact equivalence depends on technology β€” an EFB cannot be replaced with a conventional battery in Start-Stop devices. See the "Equivalents" section to view recommended options at the same performance level. ## Reviews - **Average rating**: 4.79 / 5 (52 reviews) ## Technical team (editorial authorship) The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team β€” over 25 years of experience validating automotive batteries. β†’ https://baterias.com/gb/technical-team --- *baterias.com β€” Automotive batteries Β· 2026-09-28*