D23-12V-850 Sodium-Ion Battery: Group D23 Starter Specifications for B2B Buyers

The NaVolt D23-12V-850 is a 12V sodium-ion starter battery with an approved cold-cranking rating of 850A, a maximum continuous discharge current of ≤40A, a maximum continuous charge current of ≤20A, and a maximum envelope of 231 × 175 × 222 mm (W × D × H) at 6.52 kg ±0.5 kg. Those figures settle most first-round screening questions. They do not settle fitment: the D23-12V-850 is a group D23 footprint candidate for starter applications, but it is not declared as a drop-in replacement for any specific AGM or EFB part number, so terminal type, hold-down arrangement and vehicle-level compatibility have to be confirmed with engineering before a trial order.

Buyer summary and scope

This page is written for procurement engineers and fleet maintenance managers who need to decide whether the D23-12V-850 belongs on a shortlist and what to verify before spending sample budget. It covers the approved specification set, the meaning of each current rating, the charging and cutoff limits that constrain system integration, and the dimensional checks that decide whether a physical trial is even possible.

What this page is not: a vehicle application list. No make, model or terminal configuration is asserted here as compatible. Any statement of that kind has to come from a written engineering confirmation covering your specific application.

The approved headline figures are:

• Nominal voltage: 12V
• Cold cranking amps (CCA): 850A
• Maximum continuous discharge current: ≤40A
• Maximum continuous charge current: ≤20A
• Maximum dimensions, W × D × H: 231 × 175 × 222 mm
• Weight: 6.52 kg ±0.5 kg
• Charging voltage: 15.8V
• Discharge cutoff voltage: 6V
• Storage temperature range: 0 °C to 45 °C

Full model detail sits on the NaVolt D23-12V-850 product page.

Approved D23-12V-850 specification table

The table below is the reference set for quotation and design review. Values are stated in the units used for the approved data, so they can be copied into a specification sheet without conversion errors.

Parameter	Approved value	Unit or condition
Nominal voltage	12V	Nominal pack voltage
Cold cranking amps (CCA)	850A	Cold-cranking rating, not a continuous current
Maximum continuous discharge current	≤40A	Continuous, 1C reference
Maximum continuous charge current	≤20A	Continuous, 0.5C reference
Charging voltage	15.8V	System charging setpoint
Discharge cutoff voltage	6V	Pack-level cutoff, not zero-volt operation
Maximum dimensions (W × D × H)	231 × 175 × 222 mm	Maximum envelope, width × depth × height
Weight	6.52 kg ±0.5 kg	Including tolerance
Rated capacity	40Ah ±5%	25 °C, standard charge/discharge
Internal resistance	≤4mΩ	Between discharge terminals
Charging temperature range	-20 °C to 45 °C	Operating window, charge mode
Low-temperature charge limit	0.1C between 0 °C and 5 °C	Reduced rate below 5 °C
Discharging temperature range	-45 °C to 60 °C	Operating window, discharge mode — not a cold-start rating
Storage temperature range	0 °C to 45 °C	Storage mode only

The specification table and the procurement checklist both draw on the same source: the D23-12V-850 product datasheet page.

Every parameter in this table is taken from the approved D23-12V-850 data set, including rated capacity, internal resistance and the separate charging and discharging temperature windows. Figures that do not appear here — such as capacity at other discharge rates, cycle life or cold-crank results at specific temperatures — are outside this document. Request them on the current datasheet and have them confirmed in writing for your project, rather than inferring them from a similar model in the range.

What 850A CCA means and what it does not mean

Cold cranking amps is a test result, not a capability ceiling. A CCA figure describes the current a battery can deliver for a defined discharge duration at a defined low temperature while staying above a defined end-of-discharge voltage. All three conditions belong to the test definition; change any one of them and the number no longer applies. When the D23-12V-850 is quoted at 850A CCA, that value should be read together with the test standard printed on its datasheet.

Three distinct quantities are often collapsed into one number in early-stage comparisons. They should stay separate:

• Cold cranking (850A) is a short, high-current burst under cold conditions, used to turn an engine or start a comparable load.
• Maximum continuous discharge (≤40A) is the steady current the pack is rated to supply over sustained operation, such as accessories, telematics, refrigeration or inverter loads.
• Maximum continuous charge (≤20A) is the steady current the pack is rated to accept during recharge.

So 850A CCA is neither a continuous discharge nor a continuous charge rating, and peak current is a third, separate quantity with no approved figure — see the FAQ below for the boundary in full.

One more distinction matters for catalogue work. The model code does not, by itself, define the CCA rating. Model names in this range are not a decode key for cranking current, so always cite the approved 850A figure from the datasheet instead of deriving it from the naming convention. That convention also protects you from copying a neighbouring model's data into a D23 quotation.

In practice, a starter battery spends most of its life at low current and a small fraction of it at cranking current. Screen the D23-12V-850 against both profiles: match cranking demand against the CCA rating, then match the duty cycle of parasitic and accessory loads against the ≤40A continuous discharge limit.

Charging voltage, cutoff voltage, and thermal limits

The approved charging setpoint is 15.8V, and the low-temperature charge limit is a further constraint: between 0 °C and 5 °C, charge at 0.1C rather than the normal rate. Below the charging window of -20 °C, charging is outside the approved envelope.

Three numbers constrain how the D23-12V-850 integrates with an existing electrical architecture.

Charging voltage: 15.8V. This is the approved charging voltage for the model. Before sampling, compare it with the actual regulation setpoint of the alternator or DC-DC converter in the target application, including any temperature-compensation behaviour. A system that regularly pushes above the approved value is a design conversation, not a battery-selection conversation.

Discharge cutoff voltage: 6V. The pack is specified with a 6V discharge cutoff. It is not a zero-volt product, and describing it as one is incorrect. Applications with long standby periods, deep parasitic drains or uncontrolled discharge should include low-voltage protection so that the pack is not taken below the approved cutoff.

Maximum continuous charge current: ≤20A. This is the steady recharge limit. It is independent of the charging voltage figure and independent of the CCA rating.

Thermal handling is where most integration assumptions go wrong. The approved storage range for the D23-12V-850 is 0 °C to 45 °C, which constrains how the battery is warehoused, shipped to site and parked before installation. Storage range is not the same thing as operating range. The approved operating windows are separate and both appear in the specification table: charging from -20 °C to 45 °C, and discharging from -45 °C to 60 °C. The discharge window describes the temperature range over which discharge is specified; it is not a cold-start rating and does not certify an engine start at any particular temperature. Match both windows against the climate the vehicle actually operates in, and confirm cold-crank behaviour with NaVolt engineering for the target engine.

For cold-climate fleets this drives a concrete policy question. If vehicles are parked or charged below the window the datasheet confirms for charging, the charging strategy — not the battery model — needs to change, for example by delaying charge until the pack has warmed. A CCA rating of 850 A describes a cold-cranking test result under defined test conditions; it is not, on its own, a statement that the product starts an engine at any particular ambient temperature, and it should not be marketed as one without a matching test report.

Run the same review at the top of the range. High under-hood temperatures affect both storage and charge acceptance, so check the mounting location against the datasheet windows before approving a trial.

Dimensions, weight, and group D23 fitment checks

Physical fit is usually the fastest way to disqualify a candidate. The D23-12V-850 is approved at a maximum envelope of 231 × 175 × 222 mm, quoted as width × depth × height, with a weight of 6.52 kg ±0.5 kg.

Treat these as maximum values, not nominal casting dimensions. In a tray comparison, the checks that decide feasibility are:

• Tray length, width and floor flatness against the 231 × 175 mm footprint, including any ribs or clamps that reduce usable area.
• Total height clearance to the bonnet, terminal cover or surrounding structure against the 222 mm maximum.
• Terminal position, post type and polarity relative to the existing harness routing; cable length and bend radius often decide the outcome before the tray does.
• Hold-down type and location, including whether the existing clamp contacts the approved case rather than a bracket from a different model.
• Service access for jump-start points, fuses and adjacent components.
• Handling and lifting provisions for a 6.52 kg ±0.5 kg unit during line-fit or workshop replacement.

Group D23 is a size reference, not a compatibility certificate. No vehicle make, model, terminal orientation or hold-down type is confirmed for the D23-12V-850 in this article. Terminal compatibility, hold-down compatibility and any BCI-style fitment claim have to be confirmed by NaVolt engineering against your drawing before a sample is committed.

For a broader method of matching group sizes to sodium-ion models, see battery group size and sodium-ion model matching.

Procurement checklist before a sample or trial order

Once the specification table, the current ratings and the envelope all look plausible, convert them into a short, evidence-based review list. Each item below should be answered in writing by the buyer's engineering team before the sample request moves forward.

1. Application current profile. Separate cranking demand from sustained load. Confirm the sustained load sits within the ≤40A continuous discharge rating, and identify any inrush event that would need a separate peak-current characterisation.

2. Charging system compatibility. Record the actual regulation setpoint and confirm it is consistent with the approved 15.8V charging voltage. Check the recharge current against the ≤20A continuous charge limit.

3. Low-voltage protection. Confirm that the application will not discharge the pack below the 6V cutoff, or specify protection that enforces it.

4. Mounting envelope. Compare the drawing against 231 × 175 × 222 mm maximum dimensions, including tolerances, and confirm hold-down and terminal arrangements.

5. Thermal environment and charging policy. Map the installation location's temperature profile against the storage range of 0 °C to 45 °C and against the charge and discharge windows on the current datasheet.

6. Documentation set. Agree which documents the trial requires — datasheet, test reports, declaration documents — and request them with the sample.

7. Trial design. Define sample quantity, trial duration, duty cycle, acceptance criteria and the person who signs off.

One discipline keeps this list honest: separate approved datasheet values from marketing statements. Claims such as sub-zero cold starting or an IP rating are frequently lifted from a brand-level page and then attached to a specific model without a matching test report. Unless a claim is issued against the D23-12V-850 itself, it should not enter a procurement comparison. The same applies to performance comparisons against AGM or EFB batteries: without approved comparative data, keep the discussion on the numbers in the table.

For help translating an application profile into a model shortlist, see how to choose a sodium-ion starter battery.

How to request the D23-12V-850 datasheet or sample quotation

The fastest route to a usable quotation is a single message that already contains the engineering context. Use the NaVolt contact page and include:

• The application type and duty cycle, with cranking and continuous load figures separated.
• The target battery envelope and available mounting space, with a drawing if one exists.
• The charging system type, regulation setpoint and recharge current available.
• The operating climate, including the lowest expected charging temperature.
• Required documentation and any approval deadlines.
• Sample quantity and the date by which the trial must start.

With those inputs, the response can confirm the approved specification values, flag any parameter that needs separate characterisation, and state clearly which fitment questions remain open. That is a more reliable basis for a trial order than a generic catalogue request.

Primary action: request the D23-12V-850 datasheet or a sample quotation.

FAQ

What are the approved D23-12V-850 specifications?

The approved set is: nominal voltage 12V; CCA 850A; maximum continuous discharge ≤40A; maximum continuous charge ≤20A; charging voltage 15.8V; discharge cutoff voltage 6V; maximum dimensions 231 × 175 × 222 mm (W × D × H); weight 6.52 kg ±0.5 kg; storage temperature 0 °C to 45 °C. Rated capacity, internal resistance and both temperature windows are part of the approved set and are listed in the specification table above. Capacity at other discharge rates, cycle life and cold-crank results at specific temperatures are not, and should be requested on the current datasheet.

Does 850A CCA mean the battery can supply 850A continuously?

No. CCA 850A is a cold-cranking test result defined by a low temperature, a discharge duration and an end-of-discharge voltage. Continuous current is a separate rating: maximum continuous discharge is ≤40A and maximum continuous charge is ≤20A. Peak current is a third, separate quantity, and no approved peak-current figure is published for this model.

Is the D23-12V-850 a direct drop-in replacement for a group D23 AGM battery?

It should be treated as a group D23 footprint candidate, not a declared drop-in replacement. No vehicle make, model, terminal orientation or hold-down type is confirmed for this product here. Terminal compatibility, hold-down compatibility and application fitment must be confirmed with NaVolt engineering before sampling.

What is the discharge cutoff voltage?

The approved discharge cutoff voltage is 6V at pack level. The product is not specified for zero-volt operation, so applications with long standby drains should include low-voltage protection to keep the pack above the cutoff.

What charging voltage should the system provide?

The approved charging voltage is 15.8V. Confirm the alternator or DC-DC converter setpoint, including temperature compensation behaviour, against that value, and check the available recharge current against the ≤20A continuous charge limit.

What should a buyer prepare before requesting a sample?

Prepare the application current profile with cranking and continuous loads separated, the charging system details, the mounting envelope and available space, the operating climate with the lowest expected charging temperature, the required documentation set, and the trial timing and quantity. Sending these together shortens the path from enquiry to a usable sample quotation.