Reddit mentions: The best boat battery chargers
We found 10 Reddit comments discussing the best boat battery chargers. We ran sentiment analysis on each of these comments to determine how redditors feel about different products. We found 8 products and ranked them based on the amount of positive reactions they received. Here are the top 20.
1. Sterling BB1230-12 Volt, 30 Amps - Pro Batt Ultra Battery to Battery Charger
- WARNING: Not to be confused with Sterling PCU models (Sterling Pro Charge Ultra Battery Chargers)
- 4 stage battery charging. The B2B charges batteries between 5-20 times faster than a stand alone alternator
- OEM lock: the unit can be locked by the installer to prevent tampering and misuse of the product by the operators. By locking the BB, you secure all previous settings in place and prevent subsequent tampering
- Unit is current limiting, prevents large current flow and requires less cable thickness
- B2B turns on at 13.6V and turns off at 13.3V (x2 for 24V). Thus, does not drain input battery. Regenerative braking mode shall allow the input voltage to drop to 12.2V (x2 for 24V).
Features:
Specs:
Height | 4.49999999541 Inches |
Length | 7.99999999184 Inches |
Number of items | 1 |
Weight | 2.9982867632 Pounds |
Width | 7.99999999184 Inches |
2. Sterling Power USA Pro Alt C Alternator to Battery Charger 12V 130A
Turn your alternator into a 4 stage battery chargerIntegral split charge facility - 1 output to starter, other output to houseProgrammable for AGM, Gel, flooded, sealed, calciumTypically 5 times faster than a standard alternatorNo ECU problems, doesn't void alternator warranty. Pays for itself in a ...
Specs:
Color | Grey / Red |
Height | 3.09842519369 Inches |
Length | 10.59842518604 Inches |
Number of items | 1 |
Weight | 5.4895103238 Pounds |
Width | 6.99999999286 Inches |
3. ProMariner 43012 ProSport 12 12 Amp, 12/24 Volt, 2 Bank Generation 3 Battery Charger
- 2 Year Warranty
- Energy Saver Mode
- Storage Recondition Mode
- Built-in Quality and Safety
- Distributed-On-Demand Technology
Features:
Specs:
Color | Beige |
Height | 9.875 Inches |
Length | 7.25 Inches |
Number of items | 1 |
Release date | January 2019 |
Size | 1-(Pack) |
Weight | 5.9 Pounds |
Width | 2.75 Inches |
4. ProMariner 63170 ProNauticP Series 2420P - 24 Volt, 20 Amp Battery Charger
- Up to 12 performance & Precision 4-stage charging profiles: charge, condition, maintain and Re-Condition. Automatic dockside power mode for 12 Volt DC lighting and appliances. Factory set For flooded (lead acid) batteries. Agm, gel selectable.
- Auto-ranging (100-250VAC/50-60Hz) global AC input with reduced harmonic distortion allowing all models to operate off a household power outlet connection. ProNauticP consumes less power so more AC power is available on board.
- Automatically Programs conditioning time Based on discharge State of batteries. Automatically de-sulfates batteries after 21 days in the maintain mode, improving reserve power performance & extending battery life.
- Real time indication of wiring faults or adverse conditions that may impact the operation of a boat’s charging system.
- Up to 12 performance & precision 4-stage charging profiles: Charge, Condition, Maintain and Re-condition. Automatic dockside power mode for 12 Volt DC lighting and appliances. Factory set for Flooded (Lead Acid) batteries. AGM, GEL selectable.
- Auto-ranging (100-250VAC/50-60Hz) global AC input with reduced harmonic distortion allowing all models to operate off a household power outlet connection. ProNauticP consumes less power so more AC power is available on board.
- Automatically programs conditioning time based on discharge state of batteries. Automatically de-sulfates batteries after 21 days in the maintain mode, improving reserve power performance & extending battery life.
- Real time indication of wiring faults or adverse conditions that may impact the operation of a boat's charging system.
- After 72 hours of not seeing a load greater than 5 amps, float voltage will be lowered consuming less energy during storage periods. (for flooded & sealed charge profiles)
Features:
Specs:
Color | Black |
Height | 5.75 Inches |
Length | 12.63 Inches |
Number of items | 1 |
Size | One Size |
Weight | 6.2 Pounds |
Width | 10.5 Inches |
5. Sterling Power USA Pro Alt C Alternator to Battery Charger 12V 210A
- Turn your alternator into a 4 stage battery charger
- Integral split charge facility - 1 output to starter, other output to house
- Programmable for AGM, Gel, flooded, sealed, calcium
- Typically 5 times faster than a standard alternator
- No ECU problems, doesn't void alternator warranty. Pays for itself in a matter of weeks due to gas saved.
Features:
Specs:
Color | Grey / Red |
Height | 4.49999999541 Inches |
Length | 13.49999998623 Inches |
Number of items | 1 |
Weight | 7.6941329438 Pounds |
Width | 11.49999998827 Inches |
6. attwood 9065-1 Standard Battery Box - 24 Series, Vented
- Standard battery box
- Fits Series 24 batteries (10-1/8" maximum height)
- Four cable openings, enlarged to 0.55" diameter
- Large handles with rolled edges
- Instructions molded inside cover
- New larger capacity! Vented and non-vented battery box for standard size, series 24 batteries (10-1/8" maximum height)
- No mounting hardware is included with white models. Note: 9069 cover is non-vented and is not for marine use.
- Battery boxes meet ABYC standard E-10 and U.S. coast guard specification number 183.420 as an OEM-installed battery hold-down system
- Polypropylene construction for total acid resistance. Hold-down straps resist 350 pounds of force, nearly four times the USCG requirement.
- Battery Boxes are drop tested in temperatures ranging from -20DegreeF to +120DegreeF. Mounting hardware is included.
Features:
Specs:
Color | Unspecified |
Height | 20.99999997858 Inches |
Length | 14.9999999847 Inches |
Number of items | 1 |
Release date | January 2018 |
Size | One size |
Weight | 2.1 Pounds |
Width | 18.99999998062 Inches |
7. BMK 12V 5A Smart Battery Charger Portable Battery Maintainer with Detachable Alligator Rings Clips Fast Charging Waterproof Trickle Charger for Car Boat Lawn Mower Marine Sealed Lead Acid Battery
【UPGRADED DEFECTIVE BATTERY DETECT/FAST CHARGING CAR BATTERY BOOSTER】Updated with battery condition diagnose to detect the defective battery before charge. DC Output 13.8V/5A, AC Input 100-240V, 1.5A 60/50Hz; With 5A DC output current, BMK 12V 5A car battery charger is suitable for charging batt...
Specs:
Color | 12V@5A |
Weight | 0.991875 Pounds |
8. MinnKota MK-2-DC Dual Bank DC Alternator Charger
Included Components: Minn Kota 1821032 On-Board Dc Alternator Charger - 2 BankSport Type: Fishing
Specs:
Color | Black |
Height | 5 Inches |
Length | 16 Inches |
Number of items | 1 |
Release date | July 2011 |
Size | 10 amps |
Weight | 5 Pounds |
Width | 9 Inches |
🎓 Reddit experts on boat battery chargers
The comments and opinions expressed on this page are written exclusively by redditors. To provide you with the most relevant data, we sourced opinions from the most knowledgeable Reddit users based the total number of upvotes and downvotes received across comments on subreddits where boat battery chargers are discussed. For your reference and for the sake of transparency, here are the specialists whose opinions mattered the most in our ranking.
Yeah, you'll definitely want more. However, I sort of question how much battery capacity you have to begin with. That's ALOT. What are you running?
If you could cut some capacity (and space/weight), it would allow you to top off the smaller amount easier, which is probably better for their longevity. Keeping them at a continual partial state of charge is much worse than closer to full.
I figure daily solar/alternator should be able to cover 1.5-2 days of usage, and battery capacity should cover 3-4 days usage (to make up for days when you don't drive/have sun).
And no, the issue isn't with the alternator - the limiting factor is the current that the batteries themselves can accept. The alternator is probably running at 10% output when they get to 85% SOC. I dont know the specs of the CTEK unit, but I suppose it is possible that if a device were to trick the alternator into outputting higher voltage and/or convert it to a higher voltage, then more current would flow into the batteries. I know in the marine world people get some pretty fancy (and expensive) alternator regulators that have multi-stage charging profiles which presumably give a little extra speed. But it doesnt seem like an economical choice to be honest, and surely has efficiency losses that would negate some of the benefits. I'd rather put the money towards another solar panel or two.
One device that I had looked into, but didnt end up getting because I got lithium batteries and needed a different setup, was this:
It seems much more promising than the CTEK units that I've seen around here. It actually does what I was saying - tricking the alternator and converting voltages to optimal levels.
But again, I'd just get more solar.
Yes I think getting the batteries to a known state is the best first step. Once they're fully charged by a decent charger you can just let them sit 24hrs and see what the voltage is then. Healthy batteries should settle down to 12.6v after being disconnected from the charger. If they go much lower, or more to the point if they continue dropping below 12.3 while they're disconnected then they're bad and probably can't be recovered.
A trickle charger won't do it though, you need something that has a setting for sla vs flooded batteries and that can drive at least 10A and you need a voltmeter and ammeter, built in is best - some way to continuously monitor the progress. If it's not a quality 3-stage charger then just watch it as the voltage rises to 14.4-14.5 and then watch for the amp draw to fall off. The rule I go by for terminating charging is 5% of the 20 hour amps capacity rating of the batteries. If those are 100AH for 20 hours rated then that's obviously 5A. When the charge current drops to 5A you're done with that one.
Note that most solar charge controllers require that the solar inputs to the controller never be active unless there's a battery connected on the battery side first. I blew up a Chinese controller this way once though not nearly as nice a one as you have there ($12 on Amazon).
Any 10A or bigger charger will work provided it can be set for sla batteries
These following units are cheaper on marine sites. Just google the model number.
A good one:
https://www.amazon.com/ProMariner-43012-ProSport-Generation-Battery/dp/B00F5EBR1C/ref=mp_s_a_1_7
A superb charger for permanent install as generator driven backup to your solar:
https://www.amazon.com/ProMariner-63170-ProNauticP-2420P-Battery/dp/B004S63NIS/ref=mp_s_a_1_4
Have you seen this?
Sterling BB1230-12 Volt, 30 Amps - Pro Batt Ultra Battery to Battery Charger https://www.amazon.com/dp/B071DMV7PF/ref=cm_sw_r_cp_api_i_Xg9RCb3FA8T5T
Its able to charge LFP AGM etc, theres only 2 reviews and one is probably from the company, but it seems like a great solution. The issue is that its not readily set up for direct solar hookup and you need an extra MPPT charge controller for that.
I've got similar electrical needs to you, currently move between inverness and the central belt and have 290w on the roof. There have a couple times where it's been dreary for a few days and the batteries have rundown near to 50%, so in those events I've limited my usage and gone for a wee drive the next day. Hasn't happened too often though.
If you're driving every day you might be fine without solar but I would look in to a proper battery charger like one of these (https://www.amazon.com/Sterling-BB1230-12-Volt-30-Amps/dp/B071DMV7PF/ref=sr_1_1?ie=UTF8&qid=1535726827&sr=8-1&keywords=sterling+bb1230). I only mention it because my 'smart' relay only pushes 14.6v in to the batteries which isn't enough for an equalize charge and they'd end up dieing prematurely if it was the only charging source.
I'll plug this fridge too as it's awesome and uses very little power.
I went with one of these.
Highly recommended by other dwellers and This blog has a great review on it.
To run your AC (and everything else, although they're really negligable) that long, you're going to need 37 100w solar panels. That's probably not going to fit on your bus, and by the sounds of it, it definitely won't fit your budget. Also, that 100w rating assumes that these panels are at a 90 degree angle to the sun. So, you'll need to tilt the panels. That also assumes you don't have losses from a crappy PWM solar controller. So, you're going to need MPPT controllers, which are expensive ($550 and way up). And you'll run four 6v Trojan T-105REs down to damaging levels in just two hours.
So, you're best bet is to either use your bus' engine as a generator, in which case I suggest an alternator to battery charger (These get much more power out of your alternator than a simple isolator will. They are well worth the money.) or buying a generator tied to a charge controller (You'll want/need the charge controller if you plan on plugging in anywhere anyway). The generator is by far more efficient (quieter and smells better), but you'll have to find a place for it, and store gasoline for it. It's more expensive up front, but cheaper in the long run.
Another tip would be to get a smaller AC unit. I'm in Texas where the weather is just as hot, if not as humid, and I'm running two 6,000btu window units. That way I can run one when I need to conserve power, and two when I can plug into "shore power" at a camp site or friend's house. New window units are cheap. And running just one of those will only cost you 7kW for the day instead of the astronomical 26kW you're talking about. I think my whole central air system at home uses less than 26kw a day, and I like it COLD!
With my setup that I'm building currently, I'm going to run the alternator to battery charger for when I'm driving (free power), 4x 250W solar panels on tilting racks, a MidNite Solar Classic 200 MPPT solar controller, a 3000w inverter/charge controller combo, 8x Trojan T-105REs, and a 30A shore power plug. I expect my total setup to cost me just under $5k. I also intend to add a second set of solar panels and solar controller next year to get another 1kW of solar up to need to run the bus engine less often.
Amazon sells decent boxes for this.
​
In my 93 I just ratchet strapped a square milk crate to mine and kept jumpers and chains in it mostly.
or charge with:
https://www.amazon.com/dp/B06XK7PM9F/ref=sxts_sxwds-bia_1?pf_rd_m=ATVPDKIKX0DER&pf_rd_p=d754fdf0-fd52-4edd-8917-8e65a84c20d5&pd_rd_wg=7nQKl&pf_rd_r=YS6V4J7WZ257BVW0RJ7S&pf_rd_s=desktop-sx-top-slot&pf_rd_t=301&pd_rd_i=B06XK7PM9F&pd_rd_w=zoiM2&pf_rd_i=12v+charger&pd_rd_r=3b5f51d8-6f17-4df7-a9a2-9e9a335d1413&ie=UTF8&qid=1535782504&sr=1
To do specifically what you want use this:
https://www.amazon.com/MinnKota-MK-2-DC-Dual-Alternator-Charger/dp/B001PTHKJY/
That's how my trolling battery gets charged
Manual switches are bad cos they are manual and you tend to forget...