Short answer - No it’s not necessary.
Most people ask about maintenance chargers because they’re used to using lead-acid batteries. The chemical composition of lead-acid batteries means that they do NOT like to sit at partial charge. A couple of months on partial charge will result in irreversible damage. Lead-acid trickle chargers are therefore necessary to keep the battery topped up at all times.
Our LiFePO4 cells on the other hand, prefers to sit at partial charge rather than being completely full. It’s actually the happiest below 85% charge. Anything over that for extended periods adds undue stress to cells and can lead to premature wear. LiFePO4 chargers are therefore designed with these characteristics in mind - but keeping it always connected is quite unnecessary.
Also our batteries are smart batteries (unlike lead-acid batteries). It is managed by an onboard battery management system (BMS) which balances voltage between cells and provides protection from short-circuiting and over/undercharge. This makes our battery maintenance free. For example, it will shut down if over-drain is detected protecting it from damage. If this happens, all you need to do is plug it into a lithium battery charger - get a bit of juice back and good as new.