Switching From Tubular to Lithium: What to Know

Most people do not switch to lithium because they read about it. They switch because their tubular bank has died again, sooner than expected, and they are standing in front of the quote for the next one wondering whether there is another way.

There is, and the change is more straightforward than people fear. But there are three things that must be handled properly, and getting the third wrong is how a good battery gets ruined in its first year.

What you keep

Your panels, if you have them. Your wiring, mounting and consumer unit connection. Often your cabling, though it should be checked.

None of that cares what chemistry is in the box, which is why this is usually a smaller job than replacing the whole system.

What changes, and usually shrinks

Less battery, physically and in rated capacity, for more usable power.

Tubular should not be taken below about half its capacity if you want it to last, so a large bank was only ever giving you half of what you paid for. Lithium can be taken to eighty or ninety per cent daily. Which means a smaller lithium battery replaces a bigger tubular bank and still gives you more to use. We ran that arithmetic in lithium vs tubular.

People are usually surprised by how much floor space they get back.

The part that must be right: the charge settings

This is where switches go wrong, and it goes wrong quietly.

Tubular and lithium want completely different charging. Tubular is charged to a higher voltage, held there to finish, and given a periodic equalisation charge that would be actively harmful to lithium. Leave an inverter on its old tubular profile and it will overcharge your new battery every single day.

Nothing alarms. Nothing looks wrong. The battery simply ages far faster than it should and somebody blames the technology two years later. The correct parameters are in inverter charge settings, and this must be done on the day.

Will your existing inverter take it?

Many will. Some will not, and it is worth knowing which before you buy.

The inverter needs a lithium charge profile, or enough manual control to set one. Communication with the battery’s management system is better again, because then the battery tells the inverter what it wants instead of relying on numbers somebody typed in.

An older inverter with only a fixed lead acid profile is the case where replacing it alongside the battery is the honest recommendation, however unwelcome. Better to hear that now than to find out through a shortened battery life.

What actually changes day to day

The night reaches morning, which is the whole point. Charging is faster, so a short window of NEPA or sun puts back more. There is no water to top up, no terminals to clean, no ventilation requirement in the same way.

And you get to see what is happening, because a lithium battery reports its real state of charge rather than leaving you guessing from a voltage reading.

What to do with the old batteries

Nobody thinks about this until there are four heavy lead acid units in the corridor and nowhere for them to go.

Do not put them in the bin, and do not leave them in the compound where rain gets at them. Lead acid batteries have real scrap value and there is an established trade in them here, so they are worth money to somebody rather than being a disposal problem. A good installer will take them away as part of the job or tell you exactly who buys them.

Ask about it before the work starts. It is a small thing that says a lot about who you are dealing with, and if you want us to handle it, say so when you message us on +234 809 988 9885.