Batteries
What deep-cycle batteries do you stock?
The NOMAD range, E2 and E2 ULTRA sealed AGM (12V from 9Ah up to 335Ah) and the C2 CARBON lead-carbon line, all with a 5-year warranty.
Do you sell lithium (LiFePO4) batteries?
We sell lithium chargers (like the Ultipower 12V 50A lithium smart charger) and our DC-DC units have a lithium setting, but our own battery range is quality AGM and lead-carbon - for most NZ off-grid and RV jobs a well-sized lead-carbon bank is the sweet spot on price and durability. We do have some smaller Lithium battery models as they are convenient for light weight applications.
What's the difference between AGM and lead-carbon?
Both are sealed lead-acid; lead-carbon adds carbon to the negative plate so it tolerates partial-state-of-charge cycling far better and recharges faster - the C2 CARBON is rated for very fast recharge and a much higher cycle life than standard AGM approaching lithium levels of cycles use.
Why not just go lithium like everyone online?
Lithium is lighter and cycles more, but it's dearer up front, hates being charged at low temperatures, and needs charging voltages and a BMS matched to it, treat them wrong and they can catch fire or explode. For a shed, batch or boat that isn't weight-critical, lead-carbon often wins on total cost, compatibility, safety and robustness.
How long will an AGM battery last?
The NOMAD E2 is built for a long standby design life (10 years) and carries a 5-year warranty; cycle life will depend on how deeply and how often you discharge.
How deep can I discharge a lead-acid battery?
To any depth, the smaller you discharge it and then recharge, they smaller amount of wear you will cause on the battery. All battery types wear with use and for all battery types the increase in depth of discharge causes an increase in wear. We can design systems with lead-acid battery that discharge 10% through to 100%.
Lead acid batteries can safely be discharged down to 50%
For this assumption it isn't that it's wrong, that might be specific advice for a certain person and system, but applying it to everyone doing everything with batteries in the world is wrong. If anybody says this sort of thing to you, don't listen to any further advice from them about batteries.
What charging voltage does an AGM need?
The best voltage is 14.6V absorption and about 13.5-13.8V float at 25°C, with temperature compensation. Else the range 14.4V - 14.6V absorption is ok. That's higher and more staged than a plain alternator delivers, which is exactly why house batteries chronically undercharge off an alternator.
What voltage does the C2 CARBON want?
The best voltage is 14.3V absorption and about 13.5-13.7V float at 25°C, with temperature compensation. Else the range 14.1V - 14.4V absorption is ok.
Can I mix old and new batteries in a bank?
Potentially depending on the condition and configuration of the batteries. This is advanced work and perfectly fine if designed by an engineer with the expertise. If you don't have access to expertise avoid this as it can go wrong. Easiest thing is to contact us and we will assess and design for you.
Can I mix battery chemistries?
Generally, no - AGM, lead-carbon and lithium want different charge profiles and also discharge differently, it is very rare to do this but we have designed systems in this configuration.
How many batteries do I need for my off-grid house?
It depends on daily watt-hours and autonomy days, but as a real example we've spec'd sets of two-to-four 12V 300Ah NOMAD E2 ULTRA for house and boat banks.
What's the biggest battery you do?
The NOMAD E2 ULTRA runs up to 335Ah; that size is often out of stock, so we mostly recommend customers to the 300Ah E2 ULTRA G2.
Do you sell battery boxes and racking?
Yes - rugged boxes that suit lead-acid, AGM and lithium, plus racking kitsets for 4 or 8 large batteries (e.g. E2 270/335).
Can a deep-cycle battery also start my engine?
The NOMAD E2 has high cold-cranking amps and is sometimes used as a dual-use battery for marine or motorhome, but a dedicated deep-cycle house bank kept separate from the starter is always the more reliable setup. A change over switch to connect your NOMAD battery to your starter is a useful plan B when things have gone wrong.
Why did my battery "fry itself"?
Usually chronic undercharging (sulfation) or overcharging from the wrong profile, or an old battery reaching end of life. We'll diagnose from your usage, charging setup and voltages.
How do I store batteries over winter?
Fully charge first, then keep them topped with a smart charger left on float, or give them a periodic charge once a month, a lead-acid battery left flat sulphates and dies.
What's a battery monitor and do I need one?
A shunt-based monitor shows accurate current flow and a true state of charge in amp-hours rather than estimating from voltage. On any serious bank it pays for itself by stopping deep-discharge damage.
Are your batteries safe to ship and store indoors?
Sealed AGM and lead-carbon are non-spillable and safe indoors with ventilation. Site them in a space or compartment that is not hermetically sealed.