Calcium Battery Charger (Silver Calcium Charging Tips)

Welcome to another of our deep-dives, and this time, we’re looking at the Calcium car battery and, most specifically, the Calcium battery charger.

We’ll discuss what Calcium batteries are (they can also be called Lead Calcium batteries, while  Silver Calcium batteries have near-identical properties – we’ll use these terms interchangeably) and why they’re unique.

We’ll dig into why these special nature of these batteries mean that you need to take care in your choice of battery charger. And we’ll let you know the pitfalls to avoid when Silver Calcium battery charging, as well as the charging process.

Without further ado, let’s get started!

Calcium Battery Charger

The Calcium Battery Charger: An Introduction

What even are Calcium batteries?

Calcium batteries can be called Lead Calcium or Calcium-Calcium (Ca/Ca), while Silver Calcium batteries have almost identical properties. These batteries have plates made from a Lead-Calcium-Silver alloy. A sealed Calcium battery is maintenance-free (mf).

Despite the name, a Calcium battery is still a lead-acid battery. It’s just that the antimony (which acts as a hardener) in the battery plates of normal lead-acid batteries has been replaced by calcium. Almost all of the plates are lead, with less than 1% Calcium. 

Why Calcium? Well, the addition of even a very small amount of Calcium to the Lead battery plates improves the power performance of the battery.

Not only that, it brings about some unique improvements that make it more efficient, longer lasting, highly corrosion-resistant and with better ability to maintain high starting power over time.

Silver calcium car battery

The result is a battery that improves on the Flooded technology that many other battery types use; and a precursor to EFB (Enhanced Flooded Batteries), which are also designed to cope better with being highly discharged.

Calcium batteries have some unique features and as a result should be treated differently to normal lead-acid batteries.

Advantages of Calcium Car Batteries

The advantages of Silver Calcium batteries over normal lead acid batteries are:

  • Higher cold-cranking performance – it’s estimated they have 10% higher cold cranking ability than the same size of flooded, gel, or AGM batteries (there’s also a uniqueAGM charging process).
  • Better equipped for high temperatures – they last longer in hotter climates.
  • Very low self-discharge.
  • More resistant to corrosion.
  • Reduced gassing, compared to lead-acid batteries (which have antimony in their plates).
  • Lower internal resistance – this is why they can delivery more power to start vehicles than other batteries.

In one sense they’re perfect for the modern driver who wants a battery that doesn’t need maintenance, delivers high power and can last longer when it’s not being used. 

However, Lead Calcium batteries need a high-performing, optimised charging system

In fact, it’s crucial to have such a charger to keep your Calcium battery working well. More so than for other battery types.

We explain why below.

What Do I Need To Know About Charging Calcium Batteries?

You Need A High Charging Voltage

Calcium batteries charge voltage is much higher than “normal” lead-acid batteries. You’ll need a 14.4-14.8V charging voltage.

That means don’t use a trickle charger, it just won’t charge the battery fully. It’ll struggle to make it to 50-70%, and if your battery never gets a full charge, it’s going to start to struggle sooner rather than later.

Car Battery Trickle charger

The poorer car battery chargers on the market may also struggle to reach the required voltage.

Charging voltage for other lead-acid batteries  is 2.15V-2.35V per cell, adding up to 12.9V-14.1V for a normal 6-cell battery. So you can see the required voltage is a fair bit higher for Calcium batteries.

Silver calcium batteries’ ideal charge voltage is at the higher end of the scale mentioned, 14.8V. This high voltage is necessary for the recombination process.

Recombination Process

The process where oxygen and hydrogen naturally formed within the battery cell while charging can recombine to form water.

So why no trickle chargers? Because trickle chargers can’t provide high enough voltage to completely recharge the battery.

Make Sure Your Alternator Is Working Well

While driving, the alternator will charge your battery, as is the case for all batteries. 

For Calcium batteries more than most, you’ll want to make sure your alternator is in good working order, so the voltage is high enough to charge the battery.

Don’t Let Lead Calcium Batteries Get Fully Discharged

Calcium batteries discharge rate is excellent – they’re very slow to lose charge. 

However, the flip side is that if you do let it become discharged it causes more serious harm to the battery than for other battery types.

So you’ll need to make you sure you don’t let it discharge completely. Calcium batteries can become extremely difficult, even impossible to recharge with an average battery charger, even if it’s a smart battery charger. 

That said, there are now a few battery chargers with new technology that can bring extremely discharged batteries back to life…  

Revive calcium car batteries back to life

If Your Silver Calcium Battery Does Become Highly Discharged

Your best bet for highly discharged batteries is the CTEK MXS10 battery charger. It has the most sophisticated charging system in the world – they are able to bring batteries back to life that had seemed dead, with a RECOND mode that has hefty power in reconditioning your battery.

That said, the NOCO Genius 10 (we’ve done a review of the NOCO 10) is the best for extremely discharged batteries. It has a new feature called Force Mode that can give deeply discharged batteries a kick, even those that are completely dead, at 0 volts. We like this technology a lot, as we know the reason for many, many failed attempts to charge is voltage having dropped too low.

If you’re worried about your vehicle breaking down due to the battery, another option is to keep a jump starter in the vehicle at all times.

Here’s the safest option (it’s comfortably the most likely to work even in very cold temperatures) – a review of the NOCO GB70 jump starter.

Here’s how to tell if your car battery is dead.

Take Pre-emptive Action On Sulfation

Sulfation is Kryptonite to car batteries.

But what is it?

Sulfation is the build up of lead sulfate on the battery plates, and it’s the cause of death for the vast majority of all kinds of batteries. Sulfation is a natural process that happens to all batteries, but it’s reversible (we explain how below).

Since Calcium batteries have a high voltage requirement, they’re more likely than other kinds to suffer badly from sulfation. If Calcium batteries don’t receive a high enough voltage, they’ll deteriorate very quickly due to sulfation.

Therefore, compared to other lead-acid batteries, it’s even more essential to make sure your battery is getting a good charge.

You can do this by:

  1. Making sure you don’t leave it for extended periods unused (a week is pushing it).
  2. You need to be making at least a few long-distance journeys. If you only ever use your car for short journeys, the battery will never get enough charge.
  3. Occasionally use a desulfating charger (conditioner charger) to top up charge at high enough voltage.

If you’re not meeting these criteria, we strongly advise you get a battery charger, and give the battery a full charge occasionally.

Even if you are meeting these criteria and your vehicle is getting a good charge, it will still have some sulfation developing on the plates – it’s just the nature of how batteries work, of the chemistry and physics of batteries.

Reversing The Effects Of Sulfation On Silver Calcium Batteries

As we said earlier, sulfation is reversible, by using a charger with a desulfation mode (if you want a description of how they work – see this article on how battery conditioners work). CTEK’s desulfating battery charger, the MXS 10 is the best, along with the NOCO Genius 10. 

As a guide – if the battery is getting older (more than a year old), it may start to feel the effects of sulfation.

Pulse on calcium battery desulfator

The Best Way To Maximise Car Battery Life

If you really want to take proactive action on sulfation and maximise your battery health and lifespan, you can get a desulfator.

A desulfator is not a charger (unlike a desulfating charger). It’s a device that sits on your battery permanently, and every time you drive, it puts a pulse through your battery plates, cleaning them of all the sulfation that builds up, and preventing any more sulfate accumulating. 

If you do this when you first get the battery, you may find it lasts 2-3 times longer than it would otherwise. We’ve seen it time and time again. 

This is even better than using a desulfator charger (check out the best ways to desulfate batteries), which allows sulfation to build up and then removes it periodically – naturally some sulfate can become hardened and impossible to remove.

With the desulfator, it doesn’t even give the sulfation a chance to build up, so it maximises your battery health and therefore lifespan.

Don’t Undercharge

If your silver calcium car battery never gets a full charge, acid stratification will occur. 

Acid stratification is when the sulphuric acid in the battery electrolyte (the mixture of acid and water) settles down at the bottom of the battery, causing corrosion and reduced power delivery. 

Left unchecked, this will cause your battery to deteriorate quickly.

If your battery consistently only gets charged to around 80%, that’s when this problem can occur.

You Don’t Want To Overcharge Lead Calcium Batteries

The excess charge starts to break down the electrolyte, producing hydrogen and oxygen. Therefore, the acid becomes weaker. A healthy battery has a nice, mixed-up combination of acid and water – the more you can keep it like this, the longer it’ll last and the less you’ll experience the battery’s power weakening. 

The CTEK MXS5 and MXS10 both have RECOND Mode for reconditioning batteries (including Ca-Ca) – that can effectively reverse the harms caused by both undercharge and overcharge.

Be Super Careful When Working With Calcium Car Batteries

Be cautious when charging calcium batteries (or any process involving the battery) – the voltage is small but current is extremely high. If the terminals were connected, it could produce a fire or even explosion.

Also, never use a silver calcium battery in a vehicle that’s not optimised for it.

Our Recommendation for Silver Calcium Battery Charging

The CTEK MXS10 and the NOCO Genius10 provide everything you’d need in a Calcium battery charger. 

That is, high-voltage charging that prevents becoming becoming discharged, sophisticated charging process (you can leave them on and they’ll always charge the exact amount needed), and crucially, desulfator modes that really work.

One of the two we recommend: CTEK MXS10

One of the two we recommend: NOCO Genius 10

These are your best options, but be warned, they’re not cheap. You can also check out two lower cost options: see this review of the NOCO Genius 5 UK. And we review the CTEK MXS 5.0 here. We’ve also compiled a full comparison of the NOCO 5 and CTEK 5.0.

They provide the same high-voltage, sophisticated charging system, and reconditioning functions needed for silver calcium battery charging; just with a few less features and less amperage.

Update June 2022: The CTEK CS Free is a portable charger that is a further high-quality option to charge Calcium batteries. and it doubles as a jump starter, of sorts, should you break down.

Calcium Battery Charger: A Summary

Calcium batteries really have some exceptional advantages over lead-acid batteries, including more starting power and longer shelf life.

Silver Calcium Battery Charging Comes with Great Power & responsibility

But with great power comes great responsibility, as someone once said. If you want the power of the Silver Calcium battery, the responsibility is yours to make sure you don’t let it get discharged (the right Calcium battery charger will help). 

Keep it nice and healthy and it’ll reward you with a really long lifespan – keep that nasty sulfation at bay and you’re looking as much as a few years more than you’d have expected. 

One of the two we recommend: CTEK MXS10

One of the two we recommend: NOCO Genius 10