Sodium batteries - anyone considering fitting them?

[Baralacha]

I'd never heard of sodium batteries until a recent Cruising The Cut video from Electika 2026, where they appeared to be a real thing.

Advantages over lithium are their low temperature performance, better safety, extended life and much better environmental credentials.

At the moment only Midsummer Energy seems to sell them and they are only available as a 45V, 4.5kWh rack mount housing product, clearly designed for home installation. Your solar/ alternator controller plus inverter will need either a firmware update or a new charging profile.

Anyone considering them?

Edited Thursday at 11:36 by Baralacha

[Peanut]

A UK Manufacture:

 

https://beyondbatteries.co.uk/

 

The 5kWh 48Volt rack mount, currently sold out. (£1,495.00)

[jonathanA]

5 hours ago, Baralacha said:

I'd never heard of sodium batteries until a recent Cruising The Cut video from Electika 2026, where they appeared to be a real thing.

hmmm - that would tend to make me steer away from them....  but in truth i know nowt about Sodium batteries... although AI says:-

 

"In essence, lithium-ion batteries remain the preferred choice for high-energy, portable, and weight-sensitive applications, while sodium-ion batteries are gaining traction for cost-effective, safe, and high-power applications, particularly in stationary storage and industrial sectors. Both technologies are likely to coexist, each optimized for specific use cases rather than one fully replacing the other"

 

there does seem to be some difference in power density - sodium being lower and also some voltage differences, so i suspect it will be a while before you can easily buy all the kit you need/want to use reliably in a boat at prices we want to pay !  (based on 2 mins searching on t'interweb) 

[Tony Brooks]

When these were raised a few weeks ago I got the impression that because of the bulk and lower energy density they were being aimed at very large renewable energy storage systems and home solar storage. Personally I would want to wait a few years for the technology to become common, well proven, and with no, so far, hidden gotchas.

[cuthound]

20 minutes ago, Tony Brooks said:

When these were raised a few weeks ago I got the impression that because of the bulk and lower energy density they were being aimed at very large renewable energy storage systems and home solar storage. Personally I would want to wait a few years for the technology to become common, well proven, and with no, so far, hidden gotchas.

 

So, take the claims with a pinch of salt (sodium chloride) then .. 🤣

[nicknorman]

One problem is the wide range of voltage between full and empty. Which of course is good for the trivial issue of estimating SoC, but bad for basic devices (without constant power circuitry) that will struggle to operate adequately over the wide voltage range. As with Li, if the entire system is designed from the outset for Na-ion then no problem, but it you are going to plonk a Na-ion battery into a system designed for LA, it is going to be problematic, and more so than for Li.

[jonathanA]

Just saw this on another forum I'm on.

 

Seems the USA folks are being told sodium is great for cold climes....

 

BLUETTI Pioneer Na Portable Power Station (Sodium-ion) | 1,500W 900Wh
Engineered for the Cold

Never worry about the cold again. With the Pioneer Na, you can safely charge at -15℃ (5℉) and discharge at -25℃ (-13℉) without extra prep. From ice fishing to snow camping or handling a winter blackout, it keeps your gear running no matter how cold it gets.
Note: At -25℃ (-13℉), the Pioneer Na still delivers 80% discharge capacity, powering devices up to 1,500W; Below -10°C (14°F), it can recharge up to 60% SoC.

[blackrose]

I don't really understand the advantage over Lithium? I thought good LiFePo4 batteries had heaters so that you can charge them below zero? Some of the solar, generator or alternator power will go into the heaters to raise battery temperature before charging can commence. Isn't that the way they work or have I got that wrong? 

[nicknorman]

6 minutes ago, blackrose said:

I don't really understand the advantage over Lithium? I thought good LiFePo4 batteries had heaters so that you can charge them below zero? Some of the solar, generator or alternator power will go into the heaters to raise battery temperature before charging can commence. Isn't that the way they work or have I got that wrong? 

That’s correct, although of course the heaters use up some energy. The sodium battery data sheet says it can charge up to 60% SoC below -10c. I wonder if they actually mean that (hard to obey since one doesn’t necessarily know the SoC accurately) or whether they mean charge at 0.6C.

 

Anyway with the stabilising effect of canal water I can’t see it giving any significant advantage over LiFePO4

[MtB]

7 minutes ago, nicknorman said:

That’s correct, although of course the heaters use up some energy. The sodium battery data sheet says it can charge up to 60% SoC below -10c. I wonder if they actually mean that (hard to obey since one doesn’t necessarily know the SoC accurately) or whether they mean charge at 0.6C.

 

Anyway with the stabilising effect of canal water I can’t see it giving any significant advantage over LiFePO4

 

Another benefit is that stupid Youtube bloke won't be able to make sensationalist videos claiming your batteries can spontaneously catch fire, explode and burn down your boat like the ABC boat did with no explanation. 

 

 

[jonathanA]

33 minutes ago, nicknorman said:

That’s correct, although of course the heaters use up some energy. The sodium battery data sheet says it can charge up to 60% SoC below -10c. I wonder if they actually mean that (hard to obey since one doesn’t necessarily know the SoC accurately) or whether they mean charge at 0.6C.

 

a bit odd that. 

 

I lifted these PDFs off the other forum, but for  a 'drop in' 12v battery. I couldn't see anything about charge rate and the chinglese manual isn't clear either. 

 

interestingly they are suggesting sodium-ion can be used for cranking, stating a CCA of 1500A.  that could be an advantage i suppose. 

 

I won't be rushing out to buy some 🙂

 

12V-Sodium-Ion-Starter-Batteries-Product-Flyer-March-2026.pdf Manual-for-12V-Sodium-Ion-Starter-Battery-10355-rev-B-Integration-Manual-eSTBATS12V68-31-01.pdf

[nicknorman]

15 minutes ago, jonathanA said:

a bit odd that. 

 

I lifted these PDFs off the other forum, but for  a 'drop in' 12v battery. I couldn't see anything about charge rate and the chinglese manual isn't clear either. 

 

interestingly they are suggesting sodium-ion can be used for cranking, stating a CCA of 1500A.  that could be an advantage i suppose. 

 

I won't be rushing out to buy some 🙂

 

12V-Sodium-Ion-Starter-Batteries-Product-Flyer-March-2026.pdf 502.79 kB · 1 download Manual-for-12V-Sodium-Ion-Starter-Battery-10355-rev-B-Integration-Manual-eSTBATS12V68-31-01.pdf 522.68 kB · 1 download

 

LifePO4 cells can be used for cranking too, what normally precludes this on a leisure Li battery is the limited current capability of the BMS.

[JohnE]

As I understand it, the voltage range of a sodium battery is a lot wider. A lot of system might not tolerate it

10V to 15.6V for a 12V system whereas lead-acid batteries have a range of  11.8V to 12.8V

 

 

Edited Friday at 14:54 by JohnE

[BEngo]

Pretty much any nominal 12V system is going to range from 10 V (effectively discharged battery) to 16.0 V or more (equalisation charge from a shoreline charger), so the appliances should not be too surprised.  

 

Where there might be a problem is if Na battery charging voltages are higher than the standards for automotive/recreational 12V nominal kit  but I am not familiar with the standards.

[MtB]

1 hour ago, BEngo said:

Pretty much any nominal 12V system is going to range from 10 V (effectively discharged battery) to 16.0 V or more (equalisation charge from a shoreline charger), so the appliances should not be too surprised.  

 

Where there might be a problem is if Na battery charging voltages are higher than the standards for automotive/recreational 12V nominal kit  but I am not familiar with the standards.

 

I haven't seen any sodium "drop-in" replacements for leisure LAs on the market so far. Only 48Vdc rack batteries, so I suspect there is something stopping them being brought to market. Quite likely something quirky needed to do with charging. 

[Peanut]

1 hour ago, MtB said:

 

I haven't seen any sodium "drop-in" replacements for leisure LAs on the market so far. Only 48Vdc rack batteries, so I suspect there is something stopping them being brought to market. Quite likely something quirky needed to do with charging. 

 

Recommended Charge Voltage 15.8 Volts, might need allowing for.

https://beyondbatteries.co.uk/products/beyond-batteries-sub-zro-100ah-12v-ultra-low-temperature-battery

Click through to Specification.

[Tony Brooks]

32 minutes ago, Peanut said:

 

Recommended Charge Voltage 15.8 Volts, might need allowing for.

https://beyondbatteries.co.uk/products/beyond-batteries-sub-zro-100ah-12v-ultra-low-temperature-battery

Click through to Specification.

 

😉 easy, just set the Victron charger and MPPT to do a permanent equalisation charge, because it seems no one now uses the engine to charge their fancy batteries. 😉

[Alan de Enfield]

4 hours ago, JohnE said:

As I understand it, the voltage range of a sodium battery is a lot wider. A lot of system might not tolerate it

10V to 15.6V for a 12V system whereas lead-acid batteries have a range of  11.8V to 12.8V

 

 

 

But surely, the equipment used on a 12v FLA battery system will (must) also work on 14.6 volts when the battery is being chatrged ?

[Jhon]

10 hours ago, Alan de Enfield said:

 

But surely, the equipment used on a 12v FLA battery system will (must) also work on 14.6 volts when the battery is being chatrged ?

Potentially yes, but not automatically. A sodium-ion battery can be a good replacement for lead-acid in some 12 V systems, but the important question is what voltage the sodium battery actually provides and how the equipment handles charging.

The voltage profile is Chemistry-dependent.

[Alan de Enfield]

24 minutes ago, Jhon said:

Potentially yes,

A sodium-ion battery can be a good replacement for lead-acid 

 

Surely, there is no "potentially", it is a fact that when Lead Acid batteries are approaching fully charged, the charge source will be giving around 14.6v - and occasionally (say once a week / once a month) when doing an equalisation charge could be as high as 15.5v

 

An alternator will only provide what the battery can accept.

 

If you zoom in, you'll see my Cargo alternator's regulator is 14.8v

 

 

 

According to the friendly AI (where you seem to have take your information from) you need a BMS, so you may as well go to Lithiums.

 

Why It’s Not a Simple “Drop-In”

• Voltage mismatch: Without a BMS, the charger may not see the correct SoC, leading to overcharge or undercharge.

Edited Saturday at 06:37 by Alan de Enfield

[JohnE]

4 hours ago, Alan de Enfield said:

 

Surely, there is no "potentially", it is a fact that when Lead Acid batteries are approaching fully charged, the charge source will be giving around 14.6v - and occasionally (say once a week / once a month) when doing an equalisation charge could be as high as 15.5v

 

An alternator will only provide what the battery can accept.

 

If you zoom in, you'll see my Cargo alternator's regulator is 14.8v

 

 

 

According to the friendly AI (where you seem to have take your information from) you need a BMS, so you may as well go to Lithiums.

 

Why It’s Not a Simple “Drop-In”

• Voltage mismatch: Without a BMS, the charger may not see the correct SoC, leading to overcharge or undercharge.

Be nice 🥴‼️ "According to the friendly AI (where you seem to have take your information from)"

Edited Saturday at 11:31 by JohnE

[jonathanA]

On 07/08/2026 at 17:25, MtB said:

 

I haven't seen any sodium "drop-in" replacements for leisure LAs on the market so far. Only 48Vdc rack batteries, so I suspect there is something stopping them being brought to market. Quite likely something quirky needed to do with charging. 

Look at the pdfs I dropped in a couple of posts back.... USA 12v 'drop in' sodium batteries....

Edited Saturday at 17:17 by jonathanA
Sp

[Alway Swilby]

If you have sodium batteries are all the lights powered by them orange? 

 

I'll get me coat!

[MtB]

37 minutes ago, jonathanA said:

Look at the pdfs I dropped in a couple of posts back.... USA 12v 'drop in' sodium batteries....

 

Thanks.

 

The PDF of the battery manual says some odd things about charging, given lots of sources say charge them at 15.6V.

 

"6.1 Charging & Performance • Alternator/Charging System: Maintain ~14.2 ± 0.2 V. Avoid prolonged overvoltage (>14.8 V). • External Charging: Use multi-stage chargers suitable for AGM/LiFePO4. Max voltage ~14.4 V; float 13.6–13.8 V. Limit charge current in cold conditions (<0 °C). • Equalization & Balancing: BMS handles automatically; no manual equalization needed. • Capacity Check: Use app or simple load tests; expect gradual capacity decline over years, significantly slower than lead-acid."

 

[Tony Brooks]

2 hours ago, MtB said:

• Equalization & Balancing: BMS handles automatically; no manual equalization needed.

 

It seems that LFP and thus probably sodium batteries do not stratify like lead acids and do not sulphate, so equalisation has no point and is not needed. If I am correct it would be better for them to say that.