Ownership · Maintenance

Battery care: how to make the system last

By the IsaKiel team · Lagos · Updated 16 August 2026 · 7 min read

The battery is often the most expensive single item in a solar system. Its lifespan depends heavily on how it is housed, how deeply it is discharged and how it is charged.

Some LiFePO4 packs are rated for 6,000 cycles. That can support many years of daily use, but cycle ratings are measured under specific conditions. They are not a promise that every battery will last the same amount of time in every home.

The biggest factors are practical ones: heat, deep discharge, unstable charging and leaving the battery at either extreme for too long.

The four things that shorten battery life

1. Heat is the big one

Lithium batteries generally age faster when they run hot. A pack sitting in a sealed cupboard, a roof space or a room that reaches 40°C in the afternoon can age faster than the same pack in a shaded, ventilated room.

The first step is choosing the coolest suitable location.

Put the battery in the coolest room you can. An internal wall is better than a place exposed to direct sun. Never install it in a roof void.
Leave clear air space around and above it. Do not box it in or stack things on top.
If it is in a cupboard, ventilate the cupboard with vents at the top and bottom, not one small hole.
Never install it in the same tight space as the generator.

2. Draining it too far, too often

Depth of discharge means how far down you pull the battery before recharging it.

Taking a battery to 10% every night can wear it out faster than stopping at 30%. Most hybrid inverters let you set a minimum state of charge.

A cut-off around 20% to 30% may be a sensible starting point for daily cycling, but the correct setting depends on the battery and inverter. Ask your installer to set it according to the manufacturer's guidance and show you where it is in the menu.

This is why slightly oversizing the battery is not automatically wasteful. A bigger pack doing shallower cycles can outlast a smaller pack doing deeper ones.

3. Charging from a generator badly

Charging from a generator is common in Nigeria and can be fine in principle. The problems start when the generator is too small or unstable for the charger.

Voltage can sag and frequency can vary, leaving the inverter to deal with an unstable supply. If you charge from a generator regularly, tell your installer at the design stage.

The inverter's charging current needs to be set to something the generator can actually deliver. A generator running at its limit to feed a battery charger is hard on both machines.

4. Leaving it fully charged or flat for months

Lithium batteries do not like being left at 100% for long periods, and they do not like being left flat either.

If you are leaving the house empty for months, whether you are travelling or only use the property occasionally, around half charge is a useful rule of thumb. Shut the system down properly and check the battery manual for its storage instructions.

The routine

A practical routine takes about ten minutes a month, plus one proper check each year.

How often	What to do	Why
Monthly	Look at the state-of-charge history on the inverter or app. Note the lowest point it reached.	This can reveal a load that is creeping up or a setting that has changed before it costs you extra cycles.
Monthly	Feel the air around the battery and inverter. Warm is normal. Hot is not.	Heat can be an early warning of a ventilation or connection problem.
Quarterly	Check the panels for visible dust and rinse them when they are dirty. Clean them more often when dust builds up quickly.	Dust can reduce the amount of power the system produces.
Quarterly	Check the inverter's vents and fan intakes for dust and insects.	A blocked inverter runs hot and may reduce its output.
Yearly	Have a qualified electrician check the tightness of the DC terminals and battery lugs.	Loose DC connections are a fire risk and can cause nuisance faults.
Yearly	Check the roof mounting and cable entries for rust and cracked sealant.	Water entering through the roof or cable entries can damage the system.

Panels and inverter

Panels need very little attention. Many carry a 25-year performance warranty, although the terms depend on the model.

Keep them clean, keep them unshaded and do not walk on them. On a conventional string system, a shaded panel can reduce the output of the whole string rather than losing only its own share.

Watch for a new satellite dish, an aerial or a tree that has grown since installation.

Clean the panels in the early morning or evening, when the glass is cool. Do not put cold water on hot glass in the middle of the day. Do not use abrasives. Use a pressure washer only if the panel manufacturer specifically permits it, and do not go onto a wet roof to clean them.

The inverter can need replacing before the panels do. It is electronic equipment running warm every day, so how long it lasts depends heavily on the brand, the installation and the conditions around it.

Give it airflow, keep it out of direct sun and avoid mounting it in a dusty utility area if you can.

When you take delivery

A few minutes on handover day can prevent arguments later.

Check the serial numbers on the actual units against the brand and model on your quote. The serial numbers come with the products and are used for warranty registration.
Register the warranty, or have the installer do it and send you the confirmation.
Get the inverter settings written down, including the minimum state of charge, charge current and any generator-charging configuration.
Get a commissioning record and photographs of the finished DC and AC connections.
Agree in writing who you should call about a fault in month six and in year three.

What "10 years" actually depends on

Cycle ratings are measured in a laboratory at a stated temperature and depth of discharge.

Real life in Lagos is hotter and less controlled. A pack rated at 6,000 cycles is not guaranteed to reach that number if it runs at 40°C and is drained to 10% every night. Keeping it cool and cycling it less deeply gives it a better chance of lasting beyond a decade.

The specification you buy sets the ceiling. How you house the battery and run the system decides how close you get.

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