Which Battery Charger? Flat, Lithium or Laid Up for Winter

A battery that keeps going flat, a lithium battery that stops short of full or a machine laid up for winter each needs the right charger. Decide the job first: recover, maintain, hold the voltage during diagnostics or start the engine.

The Battery Chargers range at PartsForMachines includes more than 160 chargers, maintainers, battery support units and starter chargers for 6V to 48V batteries. They come from Victron, Sealey, Draper, SIP, Sykes Pickavant and Veloris.

Battery Down to 10V: Can a Charger Bring It Back?

It can, if it is a lead-acid battery that hasn’t been flat for long and the charger has a recovery function. Disconnect any load first. The SBC8 8A charger can charge a battery from zero volts and has a sulphation repair function.

Don’t wait, though. A lead-acid battery left flat sulphates, and after a long spell it may never take a full charge again, however long it is charged. If it won’t hold a charge afterwards, or is flat again within days, have the battery tested.

Smart Charger, Support Unit or Starter Charger: Which Do I Need?

Choose by the job: charging, diagnostics or engine starting. A basic charger, such as the CHARGE106, leaves the rate to you, with switches to pick between its two charging rates. A smart charger runs through its stages by itself, then drops to a lower float voltage that keeps the battery full.

A battery support unit holds the voltage steady during diagnostics and programming, when a dip can corrupt ECU data. The SPBC40 battery support unit gives 13.5V at up to 40A and also charges.

A starter charger adds a boost to start a vehicle with a flat battery, but it draws far more from the mains when starting: 46A against 12.5A for charging on the START660.

Do AGM, Gel and Lithium Batteries Need a Different Charger?

Yes: each needs the right charging profile, so check the charger names your battery type. Gel needs a voltage-limited charger on the correct setting, because a basic charger that runs the voltage too high can shorten its life. The SPBC40 picks the profile itself for lead acid, calcium, gel, EFB and AGM batteries.

A LiFePO4 battery needs a charger with a lithium profile. Desulphation and recondition modes are made for lead-acid batteries, not lithium. The 53490 6A smart charger handles 12V LiFePO4 batteries, while the 2A 53488 and the P440 starter charger don’t list lithium at all.

Can I Leave a Smart Charger Connected All Winter?

Yes, if it is a smart charger or maintainer made to stay connected, as it switches to float once the battery is full. The AUTOCHARGE200HF 2A maintainer, for example, keeps a 1.3–60Ah battery charged through long lay-ups, with lights showing charge or float mode. Don’t leave a basic charger on unattended: it can overcharge the battery.

Keeping the battery charged matters, as lead-acid batteries slowly self-discharge in storage. A flat battery can freeze in a hard winter, while a fully charged one copes with far lower temperatures. If the battery has filler caps, check the electrolyte level now and then during long spells on charge.

What Should I Check Before I Buy?

• Battery voltage (6V, 12V, 24V or 48V), and a charger output to match
• Battery capacity (Ah), which should sit inside the charger’s battery range
• Battery type (wet, AGM, EFB, gel or LiFePO4), named on the product page
• The job: charging, long-term maintenance, diagnostic support or engine starting
• Supply and location: some starter chargers call for a 16A, 32A or 63A supply, and the IP rating should suit damp or dusty places

Browse the Battery Chargers range, or contact the PartsForMachines team by WhatsApp, telephone or email with your battery type, capacity and the job it needs to do.

Product options, delivery options and returns terms are shown on each product page. A 30-day return policy applies to eligible items.

Frequently Asked Questions

Has my battery been charged long enough?

A smart charger such as the AUTOCHARGE200HF shows when it has moved to float. To check, let the battery rest for a few hours after charging, then measure it: a fully charged 12V lead-acid battery reads about 12.6V or more.

My machine needs charging before every start: is it the battery or the charging system?

Test both before you buy anything. The DSC250B starter charger has an alternator test mode, and the 893035SP tests the battery and the starting system, showing the lowest voltage while the engine cranks.

Will a smart charger make my battery last longer?

It can help. Lead-acid batteries lose capacity if they sit part-charged for long periods, and overcharging ages them too. A smart charger brings the battery up to full, then holds it at float rather than carrying on charging.

How often should I charge a stored battery if I can’t leave a charger on?

Store it fully charged, then check its resting voltage regularly. Recharge it when it drops below about 12.4V, which is roughly three-quarters charged on a flooded 12V battery; an AGM battery reads a little higher.

What size of charger do I need?

Match the output voltage first, then check your battery’s capacity falls inside the charger’s battery range: 1.3–60Ah for the AUTOCHARGE200HF, 40–120Ah for the SBC8 and 50–1,200Ah for the START660.

Will a 13A plug run a starter charger?

Some will, but starting can need more. The P440 runs from a 13A supply, while the START420 needs 16A for starting. The PWT1000 charges from a 13A plug, but a 63A plug is recommended for jump-starting.

Can one charger look after a leisure battery and a starter battery?

Yes, if it has more than one output. The PSC125051095 12V 50A charger has a second, auxiliary output for a starter battery, and the MBC420 charges four batteries. If a split-charge relay or DC-DC charger links them, check its instructions first.

Can I use an ordinary charger while running diagnostics or coding?

Use a battery support unit. The BSCU170, for instance, supplies 70A continuously, or up to 100A for three minutes, and holds a steady voltage, set between 13V and 14.8V, through programming.

Can a charger be used in freezing or damp conditions?

Some are built for it. The 53490, for example, has a winter mode for use down to -20°C, and IP65 chargers such as the BPC121531024R are dust-tight and protected against low-pressure water jets. Never charge a frozen battery: let it warm up first.

Why do starter chargers quote different start figures?

They are measured in different ways, so compare like with like. Some makers give a peak and a lower EN figure, such as 660A peak (400A EN) on the START660, while others quote the start current into a fully discharged battery.