Batteries store a lot of energy and can supply very high currents. A short circuit can start a fire or cause burns in an instant. Safe installation follows a few simple principles. If you follow them, a battery system is safe and boring, which is exactly what you want.
Key takeaways
- Place batteries in a cool, dry, ventilated, accessible space away from sparks and heat.
- Protect every battery circuit with a correctly rated fuse or breaker close to the battery.
- Use the right cable size, tight and clean connections, and insulated tools.
- Never mix old and new batteries or different brands in one bank.
1. Where to put them
Choose a place that is cool, dry and not in direct sun, away from flammable materials and outdoor dust and water. Leave space around each unit for air and for access. Do not put batteries where a person could trip over or damage them. The floor must carry the weight of the bank, which can be heavy.
2. Ventilation
Sealed batteries produce little gas in normal use, but any lead-acid battery can release hydrogen if overcharged or faulty, and hydrogen is explosive. Keep the room ventilated and keep sparks and flames away. Lithium batteries do not release hydrogen, but they still need cooling and must not overheat.
3. Protection of the circuit
Fit a fuse or DC breaker, rated for the battery current and voltage, in the positive cable close to the battery. A DC isolator lets you disconnect the bank safely. A battery can supply enormous short-circuit current, so an unprotected cable is a fire risk. See DC and AC in a solar system.
4. Cables and terminals
Use cables of the right size and good lugs. Tighten terminals to the torque in the datasheet and check them again after the first weeks, since loose connections heat up. Use insulated tools and remove rings, watches and metal jewellery before working.
5. Do not mix
Do not connect batteries of different age, capacity, brand or type into one bank. The weakest one will limit and damage the rest. Replace a failed battery with the same type and, in a series string, consider replacing the whole string; see when to replace a UPS or solar battery.
6. Lithium batteries
Use certified batteries with a working battery management system and approved communication with the inverter. Do not use damaged, swollen or modified units. Keep to the manual for spacing, mounting and temperature. See LiFePO4 battery datasheet guide.
7. If something looks wrong
Swelling, leaking, heat, a smell or smoke means isolate if it is safe to do so, keep people away and call a technician. Do not touch a damaged battery.
Next step
If you would like us to check your battery installation, see our installation and maintenance services or contact us on the contact page.
Leave a comment