20 Best Multi Battery Trickle Chargers [2024]

Are you looking for the best multi battery trickle chargers? Based on expert reviews, we ranked them. We've listed our top-ranked picks, including the top-selling multi battery trickle chargers.

We Recommended:

# Preview Product
1 Extreme Max 1229.4023 Battery Buddy 4-Bank Battery Charger/Maintainer Extreme Max 1229.4023 Battery Buddy 4-Bank Battery Charger/Maintainer
2 Clore Automotive PL4020, Pro-Logix 4-Bank, 8-Amp (2-Amp Per Bank) Fully Automatic Smart Charger, 12V... Clore Automotive PL4020, Pro-Logix 4-Bank, 8-Amp (2-Amp Per Bank) Fully Automatic Smart Charger,...
3 DPI XCEL Gen-V 10-Channel (Multi-Bank) Battery Charger/Maintainer DPI XCEL Gen-V 10-Channel (Multi-Bank) Battery Charger/Maintainer
4 [2-Pack] FOVAL 1000mA Battery Charger, 12V Automatic Smart Charger Battery Maintainer Trickle... [2-Pack] FOVAL 1000mA Battery Charger, 12V Automatic Smart Charger Battery Maintainer Trickle...
5 Foval Automatic Trickle Battery Charger 12V 1000mA Smart Battery Charger Foval Automatic Trickle Battery Charger 12V 1000mA Smart Battery Charger
6 MOTOPOWER MP00205A 12V 800mA Automatic Battery Charger, Battery Maintainer, Trickle Charger, and... MOTOPOWER MP00205A 12V 800mA Automatic Battery Charger, Battery Maintainer, Trickle Charger, and...
7 Mroinge 12V 2A Lead Acid & Lithium(LiFePO4) Automatic Trickle Battery Charger Smart Battery... Mroinge 12V 2A Lead Acid & Lithium(LiFePO4) Automatic Trickle Battery Charger Smart Battery...
8 Battery Tender 5 Bank Battery Charger and Maintainer, 12 or 6 Volt 4 AMP for Charging Automotive and... Battery Tender 5 Bank Battery Charger and Maintainer, 12 or 6 Volt 4 AMP for Charging Automotive...
9 Car Battery Chargers, 12V 5A Smart Automotive Battery Charger/Maintainer Fully Automatic Trickle... Car Battery Chargers, 12V 5A Smart Automotive Battery Charger/Maintainer Fully Automatic Trickle...
10 Mroinge MBC010 Automotive Trickle Battery Charger Maintainer 12V 1A Smart Automatic Trickle Charger... Mroinge MBC010 Automotive Trickle Battery Charger Maintainer 12V 1A Smart Automatic Trickle...
11 NOCO GENIUS2X2, 2-Bank, 4-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car Battery... NOCO GENIUS2X2, 2-Bank, 4-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car...
12 CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V
13 NOCO GENIUS2X4, 4-Bank, 8-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car Battery... NOCO GENIUS2X4, 4-Bank, 8-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car...
14 NOCO GENIUS1, 1-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,... NOCO GENIUS1, 1-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,...
15 CTEK (56-353) MULTI US 7002 12-Volt Battery Charger,Black CTEK (56-353) MULTI US 7002 12-Volt Battery Charger,Black
16 Schumacher SP1297 Fully Automatic Battery Charger, Maintainer, and Auto Desulfator - 3 Amp, 12V -... Schumacher SP1297 Fully Automatic Battery Charger, Maintainer, and Auto Desulfator - 3 Amp, 12V -...
17 NOCO GENIUS5, 5-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,... NOCO GENIUS5, 5-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,...
18 NOCO GENIUS10, 10-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,... NOCO GENIUS10, 10-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery...
19 Charging Dock Compatible with Nintendo Switch/Switch Lite/Switch OLED Model, Compact Charger Stand... Charging Dock Compatible with Nintendo Switch/Switch Lite/Switch OLED Model, Compact Charger...
20 [4-Pack] LEICESTERCN Automatic Trickle Battery Charger Maintainer 12V 750mA Smart Float Charger for... [4-Pack] LEICESTERCN Automatic Trickle Battery Charger Maintainer 12V 750mA Smart Float Charger...
SaleBestseller No. 1
Extreme Max 1229.4023 Battery Buddy 4-Bank Battery Charger/Maintainer
  • Allows simultaneous charge of up to four 12-volt lead-acid batteries - Each cord set measures 4' 10" in length for maximum efficiency and range
  • 12V, 2A per charging bank
  • LED light indicators show battery status
  • Protection against wrong connections and short-circuiting
  • No risk of overheating charger or batteries
SaleBestseller No. 2
Clore Automotive PL4020, Pro-Logix 4-Bank, 8-Amp (2-Amp Per Bank) Fully Automatic Smart Charger, 12V...
  • 12 Volt Charging and Maintaining
  • Four independent channels. 2 amps per channel
  • Fully automatic, multi-phase process
  • Enhanced maintenance mode for long term charging
  • Includes (4) clamp output leads
Bestseller No. 3
DPI XCEL Gen-V 10-Channel (Multi-Bank) Battery Charger/Maintainer
  • Compatibility: 6, 8, 12 Volt Lead Acid, AGM Gel-Cell 4 cell Lithium Ion/Green Battery Chemistries
  • UL/CSA listed, no spark charging, reverse battery protection, 10x -4feet output leads with red/black battery clamps
  • 2x LED's per channel, LCD Input: 100-240Vac, 50/60Hz worldwide universal input
  • Output: 2Vdc to 15Vdc, 500mAdc per channel. 1inx3in214in (2.5 x 7.62x 35.8cm)
  • 3.76lbs (1.71kg)
Bestseller No. 4
[2-Pack] FOVAL 1000mA Battery Charger, 12V Automatic Smart Charger Battery Maintainer Trickle...
  • (Safety with ETL Listed): Spark proof during lead connection, reverse polarity protected and includes a 8 foot output cord and 2 year warranty
  • Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell), also Complete 4-step charging program (Initialization,...
  • Small size 3.9 x 2.4 x 1.25 in and suitable for Most Vehicles: adapts to all kinds of 12V battery for automobiles, motorcycles, ATVs, personal...
  • Intuitive LED indicators provide visual state-of-charge feedback and diagnostic information, even when in maintenance mode.
  • It will charge and maintain your battery so that it is ready to go when you are! It's lightweight, fully automatic and easy to use
Bestseller No. 5
Foval Automatic Trickle Battery Charger 12V 1000mA Smart Battery Charger
  • (Safety with ETL Listed): Spark proof during lead connection, reverse polarity protected and includes a 8 foot output cord and 2 year warranty
  • Perfect for all lead-acid, flooded or sealed maintenance free batteries (AGM and gel cell), also Complete 4-step charging program (Initialization,...
  • Small size 3.9 x 2.4 x 1.25 in and suitable for Most Vehicles: adapts to all kinds of 12V battery for automobiles, motorcycles, ATVs, personal...
  • Intuitive LED indicators provide visual state-of-charge feedback and diagnostic information, even when in maintenance mode.
  • It will charge and maintain your battery so that it is ready to go when you are! It's lightweight, fully automatic and easy to use
SaleBestseller No. 6
MOTOPOWER MP00205A 12V 800mA Automatic Battery Charger, Battery Maintainer, Trickle Charger, and...
  • 🔥【Charger, Maintainer & Desulfator】 - An all-weather battery charger, battery maintainer, trickle charger, and battery desulfator. Perfect for...
  • 🔥【Automatic Desulfation & Optimization】 - Automatic detection of battery sulfation problem. Applying with pulse current technology to desulfate...
  • 🔥【Energy Saving & Spark Free】 - Zero output in standby mode. No battery drain when connecting with the battery. Spark proof during lead...
  • 🔥【ETL/UL Certified, Multi-level Safety Protection & Timer Set Up】 - ETL safety certified. Overcharge, short circuit and reverse polarity...
  • 🔥【Easy Operation】 -Just plug-in, connect to the battery and start charging or maintaining your battery. The desulfation is working...
SaleBestseller No. 7
Mroinge 12V 2A Lead Acid & Lithium(LiFePO4) Automatic Trickle Battery Charger Smart Battery...
  • Two battery type options: 12V Lead Acid and 12V Lithium(LiFePO4); Input voltage: 100-120VAC, Output: 12V 2A
  • Multi-level safety protection: spark proof, reverse polarity, overcharging, short-circuit, over-temperature, and dust resistance. with bad battery...
  • Perfect for charging all 12V lead-acid, flooded, sealed maintenance free batteries (AGM and gel cell) and 12V-Lithium(LiFePO4) up to 85Ah, Safely...
  • Adopt 5-stage smart charging and maintains principle (Initialization, Trickle Current, Bulk Charge, Absorption Mode, Float Mode) to ensure maximum...
  • Intuitive LED indicators provide visual charging state feedback and diagnostic information. Easy connection to vehicle battery using the included...
SaleBestseller No. 8
Battery Tender 5 Bank Battery Charger and Maintainer, 12 or 6 Volt 4 AMP for Charging Automotive and...
  • 5 CHARGING STATIONS: Charge five 6 or 12 volt batteries at 4 AMPs simultaneously; automatically switches from full charge mode to float charge mode
  • BATTERY CHARGING: Charges and maintains batteries for cars, SUVs, pickup trucks, RVs, motorcycles, ATVs, personal watercraft, lawn mowers, and dirt...
  • INCLUDED COMPONENTS: This unit comes with 5 alligator clamps and a 6-foot AC power cord; charges batteries without the damage caused by trickle...
  • SAFETY FEATURES: This battery charger features reverse polarity protection, a 25-hour safety timer shutoff, and is spark proof
  • COMPATIBLE BATTERIES: Can be used with AGM, standard, GEL, and lithium batteries; charges lithium batteries at 12 volts only
Bestseller No. 9
Car Battery Chargers, 12V 5A Smart Automotive Battery Charger/Maintainer Fully Automatic Trickle...
  • 【Wide Application Charger:👍Aybe 12v automotive charger is suitable for all batteries within 6-150Ah(12V), such as Car batteries, Motorcycle...
  • 【Easy to use & Simple to connect:👍 Clear positive and negative lines, easy to connect, and have reverse polarity protection. And with Intelligent...
  • 【Battery maintainer:👍 It provides constant voltage charge for optimal maintenance of the battery. And over-charge protection enables optimal...
  • 【Multiple protection:👍 Built in circuit protection guards against reverse polarity, sparks, overcharging, over-current, open-circuits,...
  • 【LCD display:👍 Automotive smart battery charger using a backlit LCD display, clearly and visibly shows LCD screen displays charging status and...
SaleBestseller No. 10
Mroinge MBC010 Automotive Trickle Battery Charger Maintainer 12V 1A Smart Automatic Trickle Charger...
  • √ Easy To Use - Small size design, easy to install in tight places. 12V battery charger easy connection to motorcycles and vehicle battery using the...
  • √ Multi-Safety Protections - Spark proof during lead connection, reverse polarity protection, overcharging protection and short-circuit protection,...
  • √ Extend Battery Life - Perfect for charging and maintaining all 12V lead-acid batteries, including flooded, GEL, AGM, VRLA, Deep-cycle and...
  • √ Multi-Stage Smart Charging - MCU automatically controls the charging program (Initialization, Bulk Charge, Absorption Mode, Float Mode) allows for...
  • √ Compatible With Most Vehicles - Adapts to all kinds of 12V battery for cars, motorcycles, lawn mowers, ATVs, lawn tractors, trucks, SUVs, boats,...
Bestseller No. 11
NOCO GENIUS2X2, 2-Bank, 4-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car Battery...
  • Meet the GENIUS2X2 - A two-bank battery charger for charging multiple batteries. It's the all-in-one universal charging solution - battery charger,...
  • Multiple banks - A two-bank battery charger maintainer rated a 4-amps - 2-amps per bank - designed to charge and maintain multiple vehicles like cars,...
  • Do more with Genius - Designed for 6-volt and 12-volt sealed lead-acid automotive, marine, RV, powersport, and deep-cycle batteries, including...
  • Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in...
  • Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging...
SaleBestseller No. 12
CTEK - 40-206 MXS 5.0 Fully Automatic 4.3 amp Battery Charger and Maintainer 12V
  • Award-winning, Most-Trusted 12V Battery Charger: From the company that created the 12v battery charger comes tried and tested technology used by over...
  • Built-In Temperature Compensation: Built in automatic charge voltage compensation ensures the most efficient charging in extreme cold or hot weather...
  • Patented Desulphation Function and Reconditioning Mode: Unused batteries lose their power and their life is shortened through sulphation. The charger...
  • Dedicated AGM Mode: Dedicated AGM Mode sets the absorption and float voltages and stage timing so that they are optimal for AGM batteries.
  • Connect and Forget: Simple plug and play operation. Select the program and mode and leave the charger to do the rest.
SaleBestseller No. 13
NOCO GENIUS2X4, 4-Bank, 8-Amp (2A/Bank) Automatic Smart Charger, 6V and 12V Automotive Car Battery...
  • Meet the GENIUS2X4 - A four-bank battery charger for charging multiple batteries. It's the all-in-one universal charging solution - battery charger,...
  • Multiple banks - A four-bank battery charger maintainer rated a 8-amps - 2-amps per bank - designed to charge and maintain multiple vehicles like...
  • Do more with Genius - Designed for 6-volt and 12-volt sealed lead-acid automotive, marine, RV, powersport, and deep-cycle batteries, including...
  • Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in...
  • Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging...
SaleBestseller No. 14
NOCO GENIUS1, 1-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,...
  • Meet the GENIUS1 - Similar to our G750, just better. It's 35% smaller and delivers over 35% more power. It's the all-in-one universal charging...
  • Do more with Genius - Designed for 6-volt and 12-volt sealed lead-acid automotive, marine, RV, powersport, and deep-cycle batteries, including...
  • Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in...
  • Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging...
  • Restore your battery - An advanced battery repair mode uses slow pulse reconditioner technology to detect battery sulfation and acid stratification to...
Bestseller No. 15
CTEK (56-353) MULTI US 7002 12-Volt Battery Charger,Black
  • Fit Type: Universal Fit
  • Included Components: 1 Charger, Clamps, Eyelets
  • Includes two interchangeable connection leads, one with clamps, and one with eyelet terminals
  • Eight step, automatic switch charging and four separate charge modes that together allow for easy, convenient, no-watch battery charging
  • Charges 12-volt lead-acid batteries (Wet, MF, Gel, AGM and Ca) from 14Ah to 150Ah (charging) or 14Ah to 225Ah (maintenance)
SaleBestseller No. 16
Schumacher SP1297 Fully Automatic Battery Charger, Maintainer, and Auto Desulfator - 3 Amp, 12V -...
  • RELIABLE POWER: Delivers 3 Amps to charge and maintain your car, boat, or power sport batteries; compatible with standard, AGM, deep-cycle batteries...
  • SMART CHARGING: Microprocessor-controlled automatic amperage rate adjustment and multi-stage charging for added precision, safety, and battery life
  • FLOAT MODE: Float-mode monitoring automatically maintains optimum battery charge
  • HOOK ATTACHMENT: Includes hook attachment for hanging wherever you keep your tools
  • SAFE AND RELIABLE: Reverse hook-up protection prevents the charger from operating if the clamps are reversed
SaleBestseller No. 17
NOCO GENIUS5, 5-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,...
  • Meet the GENIUS5 - Similar to our G3500, just better. It's 34% smaller and delivers over 65% more power. It's the all-in-one universal charging...
  • Do more with Genius - Designed for 6-volt and 12-volt sealed lead-acid automotive, marine, RV, powersport, and deep-cycle batteries, including...
  • Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in...
  • Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging...
  • Restore your battery - An advanced battery repair mode uses slow pulse reconditioner technology to detect battery sulfation and acid stratification to...
SaleBestseller No. 18
NOCO GENIUS10, 10-Amp Automatic Smart Charger, 6V and 12V Portable Automotive Car Battery Charger,...
  • Meet the GENIUS10 - Similar to our G7200, just better. It's 17% smaller and delivers over 115% more power. It's the all-in-one universal charging...
  • Do more with Genius - Designed for 6-volt and 12-volt sealed lead-acid automotive, marine, RV, powersport, and deep-cycle batteries, including...
  • Enjoy precision charging - An integrated digital thermal sensor detects the ambient temperature and alters the charge to eliminate over-charging in...
  • Charge dead batteries - Charges batteries as low as 1-volt. Or use the all-new force mode that allows you to take control and manually begin charging...
  • Restore your battery - An advanced battery repair mode uses slow pulse reconditioner technology to detect battery sulfation and acid stratification to...
Bestseller No. 19
Charging Dock Compatible with Nintendo Switch/Switch Lite/Switch OLED Model, Compact Charger Stand...
  • 🎮 Triangle Charging stand: Compatible with Nintendo Switch Lite 2019/ Switch OLED Model 2021 and compatible with Nintendo Switch. Just put your...
  • 🎮 Safe and Stable: Designed with Over-current and over-voltage protection. Triangle stand, with the Anti-slip metal bottom as a counterweight makes...
  • 🎮 Quick Charging - This charger compatible with Nintendo Switch Lite/ Switch OLED Model 2021 charging power supply: DC15V/1.2A and compatible with...
  • 🎮 Compact Design - Compact design enables you to easily travel with the charging stand. Take it wherever! Whether on your daily commute or to...
  • 🎮 Perfect gift: This is a perfect gift for game lovers who own switch Lite, practical and beautiful. Bright colors will be a highlight and...
Bestseller No. 20
[4-Pack] LEICESTERCN Automatic Trickle Battery Charger Maintainer 12V 750mA Smart Float Charger for...
  • √ CHARGE AND MAINTAIN - Charge for all types of 12V lead-acid batteries, including flooded or sealed maintenance free batteries (AGM & gel cell). A...
  • √ 3-STAGE SMART CHARGING - Fully auto CC-CV(H)-CV(F)charging process, the battery maintenance charger monitor the whole charging process,...
  • √ INTUITIVE LED INDICATORS - With Bi-color LED indicator, CHARGING/FULL light yellow:charging, Green: fully charged/floating; REVERSE POLARITY light...
  • √ SAFETY PROTECTION & BATTERY RESUE - Just plug and leave it for charging and maintaining your batteries automatically, no worry about overcharge,...
  • √ ETL SAFETY CERTIFIED &100% SATISFACTORY FLOAT CHARGER - Certified by ETL, CE, FCC, RoHS, 3-Year quality assurance, hassle-free return or refund...

Having trouble finding a great multi battery trickle chargers?

This problem is well understood by us because we have gone through the entire multi battery trickle chargers research process ourselves, which is why we have put together a comprehensive list of the best multi battery trickle chargerss available in the market today.

After hours of searching and using all the models on the market, we have found the best multi battery trickle chargers for 2023. See our ranking below!

How Do You Buy The Best Multi Battery Trickle Chargers?

Do you get stressed out thinking about shopping for a great multi battery trickle chargers? Do doubts keep creeping into your mind?

We understand, because we’ve already gone through the whole process of researching multi battery trickle chargers, which is why we have assembled a comprehensive list of the greatest multi battery trickle chargers available in the current market. We’ve also come up with a list of questions that you probably have yourself.

John Harvards has done the best we can with our thoughts and recommendations, but it’s still crucial that you do thorough research on your own for multi battery trickle chargers that you consider buying. Your questions might include the following:

  • Is it worth buying an multi battery trickle chargers?
  • What benefits are there with buying an multi battery trickle chargers?
  • What factors deserve consideration when shopping for an effective multi battery trickle chargers?
  • Why is it crucial to invest in any multi battery trickle chargers, much less the best one?
  • Which multi battery trickle chargers are good in the current market?
  • Where can you find information like this about multi battery trickle chargers?

We’re convinced that you likely have far more questions than just these regarding multi battery trickle chargers, and the only real way to satisfy your need for knowledge is to get information from as many reputable online sources as you possibly can.

Potential sources can include buying guides for multi battery trickle chargers, rating websites, word-of-mouth testimonials, online forums, and product reviews. Thorough and mindful research is crucial to making sure you get your hands on the best-possible multi battery trickle chargers. Make sure that you are only using trustworthy and credible websites and sources.

John Harvards provides an multi battery trickle chargers buying guide, and the information is totally objective and authentic. We employ both AI and big data in proofreading the collected information.

How did we create this buying guide? We did it using a custom-created selection of algorithms that lets us manifest a top-10 list of the best available multi battery trickle chargers currently available on the market.

This technology we use to assemble our list depends on a variety of factors, including but not limited to the following:

  1. Brand Value: Every brand of multi battery trickle chargers has a value all its own. Most brands offer some sort of unique selling proposition that’s supposed to bring something different to the table than their competitors.
  2. Features: What bells and whistles matter for an multi battery trickle chargers?
  3. Specifications: How powerful they are can be measured.
  4. Product Value: This simply is how much bang for the buck you get from your multi battery trickle chargers.
  5. Customer Ratings: Number ratings grade multi battery trickle chargers objectively.
  6. Customer Reviews: Closely related to ratings, these paragraphs give you first-hand and detailed information from real-world users about their multi battery trickle chargers.
  7. Product Quality: You don’t always get what you pay for with an multi battery trickle chargers, sometimes less, and sometimes more.
  8. Product Reliability: How sturdy and durable an multi battery trickle chargers is should be an indication of how long it will work out for you.

John Harvards always remembers that maintaining multi battery trickle chargers information to stay current is a top priority, which is why we are constantly updating our websites. Learn more about us using online sources.

If you think that anything we present here regarding multi battery trickle chargers is irrelevant, incorrect, misleading, or erroneous, then please let us know promptly!

Related Post:

FAQ:

Q: What is best multiple battery charger?

A: Manual battery chargers. Manual battery chargers charge batteries continuously,but It’s very easy to undercharge or overcharge your batteries. Smart battery chargers. Smart chargers have a microprocessor inside that enables the charger to tell when the batteries are fully charged,at which point they shut off automatically. Trickle battery chargers. …

Q: When and how to use a trickle charger?

A: Switch Off Car Lights. Once you are certain the area is properly ventilated,you should then switch off the lights of your vehicle and also ensure the ignition is off. Connect The Cables. Now,you need to connect the cables and make sure the cables have the right amperage and voltage. … Turn On The Charger. … Know The Differences. …

Q: Can a battery be on a trickle charger too long?

A: Leaving a battery connected to a trickle charger for too long can lead to overcharging, causing damage to the battery. Some trickle chargers do, however, offer an automatic function to switch to a float-mode once the battery is fully charged. How long can I leave a battery on a trickle charge? The maximum safe time is 16 hours.

Q: What does a trickle battery charger do?

A: In essence, a trickle charger is a special type of battery charger designed to replenish a vehicle battery at a very low, slow rate. (The slow, gradual charging speed is actually why they’re called “trickle” chargers in the first place.) In most cases, the charge rate is about equal to the battery’s natural rate of self-discharge.