About Us


Hi, we're Terry and Margaret Covill, and we're T1 Lithium.

You might already know Terry as T1 Terry, as he's a prolific forum contributor. You can catch up with Terry and read his advice on all things lithium at OzeRVnews, Grey Nomads and a few other forums.

We've been working with lithium as house batteries for off-grid and RV use since 2011

We bought our first batch of lithium batteries in 2011 and built a number of house-power battery systems, as we wanted to see if these cells that were originally developed for electric vehicle applications could be used for off-grid house power, which is what an RV house system essentially is. Our original interest was to try and develop a battery for our 36 foot Bedford bus to run all the 240V appliances and the air con overnight.

Nobody on the interweb seemed to be able to agree on how to treat a lithium battery (Hint: forget everything you know about lead acid), what a safe charge / discharge level is, or how fast lithium could give or take charge.  

So we bought some lithium cells ("Hi Dear!  Guess what I've just spent ten grand on...!"), and we proceeded to charge and discharge - and often push until we destroyed - until we'd figured out the safe limits to return a long battery life.

In the testing process, people heard about our progress and asked for advice and some came to see us at our house near Wollongong, NSW to get some of these new-fangled lithiums installed.

Over the last eight years, we've been continuing to fine tune what we learnt in those early years. During this time, we have installed a lot of systems, done quite a number of repairs to make existing systems from other suppliers work, and have had a lot of positive feedback as we continue to offer full support to our customers.

We've developed a proven system that provides worry-free power, set-and-forget control, and freedom from the mains power grid for all our customers while offering full support that is as close as the phone or internet.

Our workshop in Mannum

In 2015 we started looking for a workshop to house our growing business and quite by accident stumbled across a workshop for sale in Mannum, South Australia, that could not have been bought for a decent lotto winning in Wollongong where we were.

So we packed up over six months (a lot of stock and vehicles to move!) and finally bought a house in October 2016.


The Ultimate Man Shed

Our loves

Green energy, electric vehicles, and glamping.

Oh, and figuring out what on earth caravan manufacturers were thinking when they installed their wiring...

© Copyright 2018 Margaret Covill trading as T1 Lithium.  All Rights Reserved.

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124 Adelaide Road

MANNUM  SA  5238

ABN 62 948 275 657

0490 049 102